Radical

Radical (from Latin radicis, genitive of radix "root") can refer to many different things and concepts.

Radical 38 or the basic "woman" character 女modern Mandarin pronunciation nǚ

Etymology

post-classical Latin radicalis relating to or forming the root, original, primary (c400 in Augustine), radical, fundamental (a1250, 1620 in British sources), of or belonging to the root of a word (1572 in the passage translated in quot. 1573 at sense A. 4a) < classical Latin r{amac}d{imac}c-, r{amac}d{imac}x RADIX n. + -{amac}lis -AL suffix1.

With use as adjective compare Middle French, French radical profound, intense, absolute (c1465), designating the humour or moisture once thought to be present in all living organisms as a necessary condition of their vitality (1516 in humide radical, 1587 in humeur radicale), relating to the root, of or from the root (1611), (in linguistics) relating to the root of a word (1660 in lettre radicale), (of a treatment) directed against the root or cause of a disease (1754 in cure radicale), (in mathematics) relating to or forming the root of a number or quantity (1762 in signe radical), advocating thorough or far-reaching political or social reforms (a1793). With use as noun compare French radical (in linguistics) root of a word (1754), (in chemistry) (1787: see below), (in mathematics) quantity that forms or is expressed as the root of another quantity (1798), person who advocates radical or far-reaching political or social reform, member of a political party or part of a party pursuing such aims (1820 with reference to politics in England, 1830 with reference to politics in France). Compare also Old Occitan radical (c1350 as adjective in humiditat radical), Catalan radical (14th cent. or earlier as adjective in humit radical), Spanish radical (c1418 as adjective in humidad radical), Portuguese radical (a1580 as adjective), Italian radicale (a1320 as adjective).

With use as noun in sense B. 2a compare post-classical Latin radicalis (1572 in the passage translated in quot. 1573 at sense B. 2a). With use as noun in sense B. 2b compare post-classical Latin radicalis (1571). In sense B. 5a after French radical (L. B. Guyton de Morveau et al. Méthode de Nomenclature Chim. (1787) 38; earlier as adjective in principe radical (1786)). The change in status of senses A. 7b , B. 6 is shown in the following two quotations: 1819 SCOTT Let. 16 Oct. (1934) VI. 2 Radical is a word in very bad odour here, being used to denote a set of blackguards [etc.]. 1842 T. P. THOMPSON Exercises I. 269 The term Radical once employed as a name of low reproach, has found its way into high places, and is gone forth as the title of a class, who glory in their designation.]

Adjective

adj. Of or relating to a root or to roots.

1. a. Of, belonging to, or from a root or roots; fundamental to or inherent in the natural processes of life, vital; spec. designating the humour or moisture once thought to be present in all living organisms as a necessary condition of their vitality; usually in radical heat, radical humidity, radical humour, radical moisture, radical sap. Now hist.

a1398 J. TREVISA tr. Bartholomaeus Anglicus De Proprietatibus Rerum (BL Add.) f. 221, {Th}e onyoun..ha{th} {th}er vnder o{th}ere rootes..and {th}erby..radical [L. radicalis] humour is ysent in to al {th}e herbe. ?a1425 tr. G. de Chauliac Grande Chirurgie (N.Y. Acad. Med.) f. 159, Sith {th}at medicynez wirke{th} by lyknes..it no{ygh}t fyndyng yuel humour noying, turne{th} it selfe to {th}e flesh and to {th}e radicale humiditeez [?c1425 Paris radical moystures]. c1460 (a1449) LYDGATE Fabula Duorum Mercatorum (Harl.) 313 in Minor Poems (1934) II. 497 Of etikes ther be kyndes thre, But oon ther is pereilous..The which is, whan..Deeply profoundid is heete natural In thilke humydite i-callyd radical. a1500 tr. A. Chartier Traité de l'Esperance (Rawl.) 21 The Power Vegetatif restith neuir..in reparing the hurte of the radicall humour. 1530 J. RASTELL New Bk. Purgatory III. vii. 2 The radycall naturall humour of that appell wyll increase whyle it is growynge. a1550 (1471) G. RIPLEY Compend of Alchemy (Bodl. e Mus.) f. 56v, Mineralls be nourisshid by mynistracione Of moistures radicall which their begyning was. 1601 P. HOLLAND tr. Pliny Hist. World I. 531 The better will she imploy her radicall sap and moisture to fructifie and yeeld good store of grapes. 1635 F. QUARLES Emblemes IV. xii. 230 Whilst thus my sorrow-wasting soule was feeding Upon the rad'cal Humour of her thought. 1643 SIR T. BROWNE Relig. Medici I. §43 Though the radicall humor containe in it sufficient oyle for seventy, yet I perceive in some it gives no light past thirty. 1713 Sin Punished 12 They deprive themselves of Sleep, consume their Radical Humour..and go down to the Chambers of Death before their time. 1772 J. W. FLETCHER Appeal Matter of Fact II. 56 His intense application hath..almost dryed up his radical moisture. 1818 LADY MORGAN Passages from Autobiogr. (1859) 235 Our wood fire scarcely suffices to keep up the radical heat. 1863 C. KINGSLEY Water-babies viii. 330 Being a water-baby, his radical humours were of a moist and cold nature. 1963 R. G. DE BRAY tr. A. Reymond Hist. Sci. in Greco-Rom. Antiq. v. 52 Perfect health corresponds to a perfect equilibrium in the proportion and qualities of the four radical humours. 2002 K. ALBALA Eating Right in Renaissance iv. 154 Aging..was seen as a process of gradually becoming drier and colder as the vital heat slowly burns the radical moisture in the body.

b. Of a quality, attribute, or feature: inherent in the nature or essence of a person or thing; fundamental. Now rare.

1562 W. BULLEIN Bk. Use Sicke Men f. 69v, in Bulwarke of Def., It doeth..consume, and waste the beste humour, or one of the radical vertues. 1611 C. TOURNEUR Atheists Trag. V. sig. K3, These bodies are depriu'd of all the radicall abilitie of Nature. 1663 J. HEATH Flagellum (ed. 2) 4 [Cromwell's] main policy was a radical and original Hypocrisie. 1744 J. THEOBALD tr. Voltaire Merope 77 He..will enquire what has been the radical Vice, and predominant Virture, of a nation. 1775 JOHNSON Taxation No Tyranny 23 The radical vigour of the Mother-country. 1806 Med. Jrnl. 15 220 The radical diversity of these rival maladies. 1828 J. M. SPEARMAN Brit. Gunner (ed. 2) p. xiv, I have pointed out..a radical error in the graduation of these scales. 1871 R. H. HUTTON Ess. (1877) I. Pref. 12 A sneer at the radical rottenness of human nature. 1920 Internat. Jrnl. Ethics 30 427 The defect is radical, and inherent in all such abstractly intellectualistic systems or modes of thought. 1988 Times Lit. Suppl. 15 Apr. 413/2 None of our individualities is radical, historyless.

2. Relating to or forming the root, basis, or foundation of something; original, primary.

a1398 J. TREVISA tr. Bartholomaeus Anglicus De Proprietatibus Rerum (BL Add.) f. 60v, {Th}e preuey stones ben..welle of humour seminal & first fundament radical {th}erof. 1553 T. PAYNELL tr. D. Phrygius Faythfull & True Storye Destr. Troye f. 1v, Dardanus, of whome the Troians toke theyr radicall and fyrste begynnyng. 1560 J. ROLLAND Treat. Court Venus Prol. 235 Idilnes is Mother Radycall, Of all vicis, and font originall. 1597 R. HOOKER Of Lawes Eccl. Politie V. lv. 117 They intimate the radicall cause out of which it groweth. a1639 W. WHATELY Prototypes (1640) I. xi. 94 This grace of faith is the radicall grace, that upon which all other graces grow as on their roote. a1676 M. HALE Primitive Originat. Mankind (1677) IV. ii. 305 Not..all those kinds which we now see,..but only those primitive and radical Species. 1755 JOHNSON Dict. Eng. Lang. Pref. {page}50 When the radical idea branches out into parallel ramifications. 1772 H. BROOKE Brief Ess. on Nature of Bogs 6 The radical reason of the difference between these two kinds of Bogs was, that the black Bog originally rose on the more luxuriant soil. 1811 J. PINKERTON Petralogy Introd. 30 The position that granite is the universally radical rock. 1871 J. MORLEY Vauvenargues in Crit. Misc. (1878) 4 A syllabus of the radical articles of the French creed of the eighteenth century. 1981 College Composition & Communication 32 422 We might find classical rhetoric taught as answers to radical or root questions a stimulating discipline. 2001 Philippine Daily Inquirer (Nexis) 21 July 7 In its most radical basis, peace is from the heart and of the heart.

Mathematics

Originally:(of a number) irrational (obs.). In later use: relating to or forming the root of a number or quantity. Now chiefly in radical sign n. at Special uses 2. 1557 R. RECORD Whetstone of Witte sig. Si, Nombers radicalle, whiche commonly bee called nombers irrationalle... Other men call them more aptly Surde numbers. 1570 J. DEE in H. Billingsley tr. Euclid Elements Geom. Pref. sig. *ij, I..do giue to this Practise, the name of the Arithmetike of Radicall numbers. 1654 S. FOSTER Elliptical Horologiography 94 Now to these two radicall numbers, I adde {oneon4} {half} {threequarters} and one whole houre. 1897 H. F. BAKER Abelian Functions 377 The most important of the radical functions are those which are square roots of rational functions. 1977 Trans. Amer. Math. Soc. 232 175 A real number x = a1/m is said to be radical if and only if a and m are positive integers.

b. Geom. Having a common relation to two or more (esp. intersecting) circles or spheres. Chiefly in radical axis, centre, plane, etc.: see Special uses 2.

1848 G. SALMON Treat. Conic Sections viii. 96 The line S - S' = O..has been called the radical axis of the two circles. 1889 J. CASEY Spherical Trigonom. 101 The circle of the system S, whose plane passes through the centre of the sphere, is called the radical circle of the system. 1968 C. B. BOYER Hist. Math. xxiv. 579 The linear pencil of circles C + {mu}C´ = 0 form an interesting ‘radical family’, whether or not C1 = 0 and C2 = 0 intersect. 1992 H. EVES Fund. Mod. Elem. Geom. i. 38 The material we are concerned about is that centered around the concepts of orthogonal circles,..the radical axis of a pair of circles, the radical center and radical circle of a trio of circles, and coaxial pencils of circles.

Linguistics

Of, belonging, or relating to the root of a word; connected with or based on a root or roots (see ROOT n.1 15); that is a root. Earliest in radical letter n. at Special uses 2; see also radical sound n., radical word n. at Special uses 2. 1573 T. TWYNE tr. H. Llwyd Breuiary of Britayne f. 8, Ther is no British woord whose first radicale letter [L. littera radicalis] is B: that abideth any change into P, or PH. 1584 J. DEE Jrnl. in Relat. Spirits (1659) I. 75 No word in his radical form is extended. 1686 Philos. Trans. (Royal Soc.) 16 69 If Calepines Dictionary were to be translated into the Chinese, 'twere necessary to have as many distinct Radical Characters as there are words therein to be found. 1724 W. GAMBOLD Welsh Gram. (1727) xliii. 114 Table of Words and Particles:..shewing what effect They have on the radical initial Letters of Subsequent Words. 1795 L. MURRAY Eng. Gram. 147 Three great principles of accentuation..the radical, the terminational, and the distinctive. 1837 H. HALLAM Introd. Lit. Europe II. i. 20 The..arrangement..[of the lexicon] is not according to an alphabetical, but radical order. 1861 F. MAX MÜLLER Lect. Sci. Lang. 275 As long as every word..is felt to express its own radical meaning, a language belongs to the first or radical stage. 1899 Amer. Jrnl. Semitic Langs. & Lit. 15 187 Verbs whose second and third radical consonants are alike. 1932 W. L. GRAFF Lang. ix. 333 When the union of radical and nonradical parts [of a word] is so great that a considerable alteration of either or both occurs, we obtain another structural type altogether, namely the fusional one. 1992 M. J. BALL & N. MÜLLER Mutation in Welsh viii. 207 Those consonants that become new initials..occur extremely rarely or not at all as radical initials. 2001 G. T. STUMP Inflectional Morphol. vi. 175 The radical stem skriv appears in the 3sg present indicative and the 2sg imperative.

b. Exhibiting the roots of words, or letters employed in those roots. Obs.

1623 W. LISLE Ælfric's Saxon Treat. Pref. 7 Huterus..in his Catalogue..before his radicall Hebrew Bible. 1756 J. ELPHINSTON Anal. French & Engl. Langs. I. ii This assemblage..exhibits..the radical dictionary of both languages.

Astrology

and (occas.) Astron. Belonging to the radix of an astrological or astronomical calculation; (of a question) asked at a time when the governing planet is also, or of the same triplicity as, a planet in the ascendant. Obs. 1621 R. BURTON Anat. Melancholy I. II. I. iv. 76 Any of those radicall promissors in the geniture. 1647 W. LILLY Christian Astrol. 121 The Question then shall be taken for radicall, or fit to be judged, when as the Lord of the hour at the time of proposing the Question..and the Lord of the Ascendant or first House, are of one Triplicity, or be one. 1654 N. CULPEPER Cent. Aphorisms in Opus Astrologium §69 sig. C5, A Radical Figure resembles either the nativity or the revolution of the nativity of the Querent. 1679 J. MOXON Math. made Easie 38 The moons coming to the..Radical place, where she was at the beginning of the sickness. 1749 J. HODGSON Theory Jupiter's Satellites 90 The Radical Places of Jupiter and his Aphelion being given for any one Year, the Radical Places of the Planet and his Aphelion may be found for any other Year, by the help of the Tables of mean Motions, for common Julian Years. 1799 J. WORSDALE Coll. Remarkable Nativities 17 The moon was posited nearly in opposition to her own radical place, and Saturn was then transitting the cusp of the ninth house. 1819 J. WILSON Compl. Dict. Astrol., Geniture, the Birth, the radical figure, the plan of a nativity.

Medicine

Of a treatment: directed against the root or cause of disease, esp. towards the eradication of tumour or infection; curative, as opposed to palliative; spec. (of a surgical operation) involving extensive resection of tissue, esp. in order to remove a primary tumour and sites of actual or potential local spread and metastasis. Freq. in radical cure. Also in fig. context. 1633 Gutta Podrica 24 Galen is of the same opinion, which is to bee understood of the perfect and radicall cure of the Gout. 1665 G. THOMSON Galeno-pale 3 In the knowledge of the Causes, Quiddity, or Essence, immediate Subject, and radical Cure of Diseases. 1735 VISCT. BOLINGBROKE Diss. upon Parties (ed. 2) 220 Such a Remedy might have wrought a radical Cure of the Evil, that threatens our Constitution. a1791 J. WESLEY Wks. (1830) XII. 131 Mr. W's radical cure I shall hardly try, I am very easy, and that is enough. 1799 W. NISBET Clin. Guide 279 The radical treatment of this affection, is conducted in a variety of ways, which may be all reduced in their action to two heads; either the simple obliteration, or actual destruction of the cavity forming the seat of the disease. 1811 T. RAMSDEN Pract. Observ. Sclerocele 212 It occurred to a surgeon of great eminence to revive the long neglected method of cure by injection, in which happily for mankind every other radical operation seems to be now concentred. 1844 Times 22 Apr. 4/3 The pinch-belly system has been adopted as a radical cure for plethoric paupers. 1926 Encycl. Brit. III. 691/2 Local excision or radical amputation is accordingly carried out depending on whether the growth has proved benign or malignant. 1968 S. TAYLOR & L. COTTON Short Textbk. Surg. (ed. 2) xv. 190 The operation of radical mastectomy involves removal of the entire breast together with the pectoral muscles and the axillary nodes and fat. 1993 Atlantic Oct. 78/1 How can we possibly justify short-term tweaking of the deficit in lieu of radical surgery to balance the budget? 2004 Seminars Radiation Oncol. 14 194/1 The combination of aggressive chemotherapy with radical irradiation leads to high rates of local control in advanced disease.

Esp. of change or action: going to the root or origin; touching upon or affecting what is essential and fundamental; thorough, far-reaching.

1648 I. PENINGTON Touchstone 15 It notes that fundamentall and radicall change which is made in the heart by the power of the truths of Christ conveyed thither, and working there. 1651 R. BAXTER Plain Script. Proof 294 Out of which Radical Regeneration..the exercised act of Faith and Graces is wont to be educed. 1739 D. HUME Treat. Human Nature I. IV. 427 Betwixt a person in the morning walking in a garden, with company agreeable to him; and a person in the afternoon inclos'd in a dungeon..there seems to be a radical difference. 1751 JOHNSON Rambler No. 171 {page}3 Desirous to fit men to his purpose by complete and radical corruption. 1802 Med. Jrnl. 8 353 A radical and systematic change of that mode of living. 1865 J. R. SEELEY Ecce Homo (ed. 8) iv. 34 Christ undertook a work more radical than that of Moses. 1874 J. R. GREEN Short Hist. Eng. People iv. §2. 171 The financial difficulties of the Crown led to a far more radical revolution in the admission into the Great Council. 1920 Times 20 Jan. 13/5 A radical change of view as to the provision for daughters..seemed to him an essential step. 1976 Glasgow Herald 26 Nov. 1/3 The system needs a radical overhaul. 2003 S. BROWN Free Gift Inside! 63 All the boring bits from the latest album, which represents a radical change of direction for the band.

Politics

Advocating thorough or far-reaching political or social reform; representing or supporting an extreme section of a party; spec. (also with capital initial) (a) Brit. belonging to, supporting, or associated with the extreme wing of the Liberal Party which called for a reform of the social and parliamentary system in the late 18th and early 19th cent. (cf. radical reform n. at Special uses 2); (b) U.S. belonging to a faction of the Republican Party seeking extreme action against the South during the Civil War and Reconstruction. Now more generally: revolutionary, esp. left-wing.

On the continent of Europe in the 20th cent., parties bearing the title of ‘Radical’ have in fact frequently tended towards a centrist or even conservative standpoint.

1783 J. MOIR Hist. Polit. Life Charles James Fox viii. 163 That the omnipotence of the state is not lodged, by the constitution, with the people, but with the whole legislative body in parliament assembled, was a radical doctrine of this obnoxious ministry. 1820 SHELLEY {Oe}dipus Tyrannus I. 12 Kings and laurelled Emperors, Radical butchers. 1832 J. S. MILL Let. 17 Sept. in Wks. (1963) XII. 117 Several friends of mine, radical-utilitarians of a better than the ordinary sort. 1835 Knickerbocker 6 92 The tendency of Americans, instead of being aristocratic, is decidedly radical. 1837 DISRAELI in Corr. w. Sister 21 Nov. (1886) 75 Wakley made a most Radical speech and amendment. 1841 S. BAMFORD Passages Life Radical I. 58 The presumptuous appearance of a radical hat. 1846 J. W. CROKER in Croker Papers (1884) III. xxiv. 90 If Radical measures were to be carried..they should be carried by Radical men. 1847 Semi-Weekly News (Fredericksburgh, Va.) 21 Oct. 2/2 The Barnburners with their ‘Radical democracy’ can never long govern this great State. 1865 Atlanta Daily Intelligencer 1 Oct. 3/1 The radical Republicans are now proposing a compromise on the negro-suffrage question. 1912 W. E. WALLING Socialism as it Is iii. 166 While one element is growing more radical another is growing more conservative and the breach between the Independents and the other Labourites is widening. 1927 W. IRWIN How Red is America? ii. 47 The half-century when the radical parties were getting their foothold in Europe and America. 1953 Manch. Guardian Weekly 1 Jan. 2 He deplored the ‘pinks’, ‘radical cliques’ and other victims of the ‘Communist line’. 1965 E. NOLTE in Rogger & Weber European Right 297 The antigovernmental Right..often attacked Hitler for being a Catholic or insufficiently radical. 2007 J. WEEKS in Sexualities & Communication in Everyday Life ii. 42/2, I want to explore in some detail this radical agenda..by exploring the trouble that radical sexual politics can cause.

c. Characterized by independence of or departure from what is usual or traditional; progressive, unorthodox, or innovative in outlook, conception, design, etc.

1869 Putnam's Mag. July 123/1 This is an encouraging symptom of the radical and searching purpose of our late American thought. 1880 Scribner's Monthly Nov. 54/2 Whitman mistakes the aim of the radical artist or poet. 1921 Daily Colonist (Victoria, Brit. Columbia) 20 Mar. 24/1 In appearance the Coats car is attractive, but not at all radical in design. 1928 E. O'NEILL Strange Interlude I. 15 He is most liberal{em}even radical{em}in his tolerant understanding of the manners and morals of Greece and Imperial Rome! 1958 Listener 23 Oct. 648/1, I would describe as radical paintings that make a difference to our ideas about art. The American contribution to radical art in this sense is particularly to be seen in the big picture. 2004 D. DATTON Rough Guide: Philippines 471 Her own independent record label..established because her tribal chanting and native instruments..were considered too radical for any major label.

Music

Of a bass, cadence, etc.: belonging to the root or lowest note of a chord. Cf. FUNDAMENTAL adj. 6. 1721 A. MALCOLM Treat. Musick xiv. 509 All the Series as well as the Extremes will reduce to radical Terms. 1753 E. CHAMBERS Cycl. Suppl. Suppl. s.v., Radical numbers..in the Italian music, are, 2, 3, 4, 5, 6, 7, 8, 9, and sometimes 10, which are often met with in musical compositions, to denote the accords of the thorough basses. 1809 J. W. CALLCOTT Mus. Gram. (ed. 2) 221 When the leading Harmony of any Cadence is not radical, but inverted, the Cadence is, in this Work, termed Medial. 1867 G. A. MACFARREN Harmony iii. 97 According to the radical progression of ascending 4ths. 1873 H. C. BANISTER Text-bk. Mus. 69 By the root of a chord, or its Radical Bass, is meant its Bass-note in its original, uninverted form. 1980 New Grove Dict. Music XV. 530/2 Radical cadence, a cadence whose penultimate and final chords are both in root position.

Botany

Of or relating to the root of a plant; esp. designating a basal leaf appearing to arise from the root (usually arising from the stem base or from a shortened stem).

1753 E. CHAMBERS Cycl. Suppl. Suppl. at Leaf, Radical Leaf, that which grows immediately from the root of a plant, not from the stalk. 1766 Museum Rusticum VI. 47 From the top of this turnep rise a number of leaves,..which answer to the radical leaves in other plants. 1851 G. F. RICHARDSON Geol. vii. 203 Leaves..proceeding from the crown or radical plate. 1861 R. BENTLEY Man. Bot. I. i. 49 On young roots we find cells..which are..of the nature of hairs, and have accordingly been termed radical hairs. 1914 F. E. FRITCH & E. J. SALISBURY Introd. Study Plants vii. 81 In many herbaceous plants..a large number of leaves arise close together from the base of the stem just above the surface of the soil; such leaves are usually collected in the form of a rosette and are termed radical leaves. 1924 A. W. SAMPSON Native Amer. Forage Plants II. vii. 115 An abundance of radical leaves is produced early in the spring, and these are highly relished by stock. 1995 Edinb. Jrnl. Bot. 52 225 Potentilla montisvictoriae differs from P. leuconota D. Don in having free auricles on the stipules of the radical leaves, [etc.].

Anatomy

Of the nature of a radicle (RADICLE n. 3). Obs. rare. 1836 Pop. Encycl. II. II. 765/2 The great portal system of the abdomen becomes loaded with blood, and congestion of its radical vessels ensues. 1846 R. DUNGLISON Med. Lexicon (ed. 6) 641/1 Radical Vessels or Vascular Radicles, (F.) Radicules vasculaires, are the small vessels that take their origin in the tissues, and by their union form larger vessels.

Slang

(a) orig. Surfing challenging; extreme; (b) (more generally) excellent, fantastic; = AWESOME adj. 3b. Cf. RAD adj.3

1964 M. FARRELLY & C. MCGREGOR Surfing Life 138 Radical, extreme. 1979 UNC-CH Slang (Univ. N. Carolina, Chapel Hill) (typescript) Mar. 6 Radical, surpassing the usual image of modern and new (positive connotation): this is a radical album. 1988 S. RUSHDIE Satanic Verses V. i. 245 ‘Radical,’ said Mishal approvingly. And her sister nodded assent: ‘Crucial. Fucking A.’ 1989 F. L. BLOCK Weetzie Bat 33 Sometimes he slept on picnic tables at the beach so he could be up at dawn for the most radical waves. 2002 WindSurfing Mar. 75/2 Comfortable for intermediates in the straights, but radical enough in the turns to satisfy hardcore slashers. 2006 National Post (Toronto) (Nexis) 10 June (Weekend Post section) 10 The dance party was, like, totally radical!

b. n.1. A part or organ of the body considered necessary to the processes of life. Obs. rare{em} 1.

?a1425 tr. G. de Chauliac Grande Chirurgie (N.Y. Acad. Med.) f. 159, {Th}u shalt nou{ygh}t lede ptisicz..to {th}e vpper purgacionz bot..lene men suple after membrez fleshlike..nou{ygh}t after radicalez [?c1425 Paris rotely membres; L. membra..radicalia] and spermatic.

Linguistics

a. A radical letter, sound, initial, etc.

1573 T. TWYNE tr. H. Llwyd Breuiary of Britayne f. 3v, B, with D, and G, radicals [L. radicales]: haue their peculiar variations... The other be neuer radicales [L. radicales], as: D, F, T, H, L, K. or els they be not changed: as PH, CH, N, and S. 1652-62 P. HEYLYN Cosmogr. (1674) Introd. 8/2 Divers Cities in that tract, which still preserve the Radicals of Hull or Chull. 1724 W. GAMBOLD Welsh Gram. (1727) ii. 2 Ch;..being a radical, is ever attended with, w. 1786 S. HENLEY in tr. W. Beckford Vathek 263 (note), On his forehead the radicals of cafer [or Infidel] are said to be impressed. 1838 N. Amer. Rev. Apr. 503 In the suffix state one vowel and one radical is dropped. 1870 J. HELFENSTEIN Compar. Gram. Teut. Lang. 410 The radical is either a or ê... The radical of the perfect is of course modified by the reduplication. 1953 Jrnl. Amer. Oriental Soc. 73 15/2 Another common characteristic is an a vowel between second and third radicals. 2000 Jrnl. Near Eastern Stud. 59 83 The nature of the original first radical of the verb ‘know’.

b. A root; a word or part of a word which cannot be analysed into simpler elements.

1621 R. CRAKANTHORPE Def. Constantine I. xi. 250 By a little inuersion of the letters (the Radicalls of Ophir, and Peru being the same) they were called each of them by it selfe Peru. 1641 J. WILKINS Mercury xiii. 109 The Hebrew..language consists of fewest radicalls. 1677 R. PLOT Nat. Hist. Oxford-shire 284 He published a Specimen..containing but 500 Radicals, all the Particles being brought from the Radicals by which they are resolved. 1740 S. LOWE French Rudim. 7 To which [terminations] it will be no difficulty at all to prefix the radicals of any word. 1797 Encycl. Brit. V. 463 The Welsh, the Cornish and the Armoric dialects, whose radicals are so much alike [etc.]. 1822 J. M. GOOD Study Med. IV. 592 It has been shown, that the real radical is the Hebrew term..(tsora). 1874 A. H. SAYCE Princ. Compar. Philol. i. 54 Words derived from the same radical will often assume different forms in different languages. 1932 W. L. GRAFF Lang. iii. 151 In Indonesian the infix -um- gives the radical a verbal active meaning. 1975 Systematic Zool. 25 192/2 This is a so-called contract noun whose radical is to be drawn from the nominative. 1988 MLN 103 1014 Phèdre... may be said to play on the radical, or root, of its prime figure: le monstre.

c. Any of the set of basic Chinese characters which, sometimes in a modified form, constitute semantically or functionally significant elements in the composition of other characters, and are used as a means of ordering and classifying characters in dictionaries; = SIGNIFIC n. Cf. PHONETIC n. 1733 London Mag. Apr. 173/1 Among the great Number of Characters in this Language [sc. Chinese], there are 400 Radicals, from whence the rest are deriv'd. 1761 Ann. Reg. 157/1 He then exhibits these Ph{oe}nician letters and the supposed correspondent Chinese radicals. 1824 J. JOHNSON Typographia II. xii. 369 Each Radical is placed at the head of a new family of characters. 1874 S. W. WILLIAMS Syllabic Dict. Chinese Lang. p. lvi/1 That part of a character which is not the radical, has no name among the Chinese, but foreigners have termed it the primitive or phonetic. 1948 R. A. D. FORREST Chinese Lang. ii. 38 After we have deducted the ‘sheep’ device from each of the three examples, the part remaining in each case is known as the ‘radical’, or better, as the ‘signific’. 1973 Sci. Amer. Feb. 54/1 A dictionary published in 1971..has merged some radicals, reducing the number to 189. 1991 Internat. Jrnl. Lexicogr. 4 II. 81 SKIP [System of Kanji Indexing by Patterns] resorts to the traditional 214 radicals (keys or semantic classifiers) which must be arbitrarily memorized.

3. A basis; a fundamental thing or principle. Now rare.

1656 R. VINES Treat. Inst. Lords-supper xxviii. 310 Covenant-benefits, Covenant graces, the radicals, the vitals. 1673 J. BUNYAN Def. Doctr. Justif. 9 And here come in those reasonable conclusions, which you would make the very radicals of Christianity, they being only remote. 1798 G. H. WATKINS Unanimity 13 These few features which I have delineated, may be also called the radicals of Gospel religion. 1808 Med. Jrnl. 19 41 Water doubtless concurs..to produce this effect, by supplying two radicals, which become assimilated to the other nutritive principles. 1833 J. HOLLAND Treat. Manuf. Metal II. 304 With reference to a similar radical, that is to say, the English penny. 1957 N. FRYE Anat. Crit. 247 We have to speak of the radical of the presentation if the distinctions of acted, spoken, and written word are to mean anything in the age of the printing press. 1982 Jrnl. Relig. 62 391 What is the primitive is..what is fundamental... It is the horizon of our perception and the radical of our being.

Mathematics

a. A quantity that forms or is expressed as the root of another quantity. Now freq. in the context of expressing the roots of a polynomial equation in terms of rational functions of the coefficients of this kind.

1714 I. NEWTON Let. in Corr. (1976) VI. 84 The method of fluxions readily gives the method of Tangents of Slusius & sticks not at equations affected with radicals. a1746 C. MACLAURIN Treat. Algebra (1748) xiv. 117 Multiply any two Radicals as 2 xy by 2 xz. 1798 C. HUTTON Course Math. II. 298 Expand the radical or fraction..into an infinite series of simple terms. 1879 Encycl. Brit. X. 48/1 Researches on the resolubility of algebraic equations by radicals. 1951 W. W. ELLIOTT & E. R. C. MILES College Math. (ed. 2) i. 4 The polynomial x2- 2 has the factors x-{sqrt}2 and x + {sqrt}2, but it does not have a factor that is free from radicals. 2005 M. LIVIO Equation that couldn't be Solved v. 144, I have investigated under which conditions the equations are solvable by radicals.

b. The radical sign, {sqrt}.

1781 Philos. Trans. 1780 (Royal Soc.) 70 401 Where the two denominators under the radicals differ by 4. 1882 C. SMITH Conic Sect. (1885) 33 It is necessary and sufficient that the quantity under the radical should be a perfect square. 1904 School Rev. 12 122 The quantity desired is concealed in the second member of an equation..or under a radical. 2001 Isis 92 129/2 Cardano's demonstrably correct formula..led to real solutions even in some instances where a negative number appeared under a radical.

Chemistry

a. Originally: an atom or group of atoms regarded as a (or the) primary constituent of a compound or class of compounds, remaining unaltered during chemical reactions in which other constituents are added or removed. Now more widely: an atom or group of atoms which behaves as a unit and is regarded as a distinct entity. Cf. RADICLE n. 2.

An individual atom or element as a constituent of a compound was formerly termed a simple radical, as distinct from a group or compound radical. The use of the word for single atoms is now unusual except in referring to free radicals (see sense B. 5b). alkyl, methyl, phenyl radical, etc.: see the first element.

1788 J. ST. JOHN tr. L. B. Guyton de Morveau et al. Method Chym. Nomencl. 58 They are all expressed by the names of their acids with with [sic] uniform terminations which are followed by the generic term radical. 1788 J. ST. JOHN tr. L. B. Guyton de Morveau et al. Method Chym. Nomencl. 58 Oxalic radical. 1806 R. PATTERSON Adams's Lect. Nat. & Exper. Philos. (rev. ed.) I. App. 531 Any simple substance which, by its combination with oxygen, becomes an acid, is termed the acidifyable base, or radical of that acid. 1815 J. SMITH Panorama Sci. & Art II. 343 Oxygen is called the radical or base of the gas. 1845 G. E. DAY tr. J. F. Simon Animal Chem. I. 141 If we knew more of the composition of the extractive matters, we should doubtless find a radical common to all of them. 1881 Nature No. 618. 415 Compounds of hydrogen with elements or radicals like chlorine. 1910 Encycl. Brit. I. 862/1 The salts produced by the action of ammonia on acids are known as the ammonium salts and all contain the compound radical ammonium (NH4). 1926 Jrnl. Amer. Chem. Soc. 48 3130 A study of the electronegativity of organic radicals is of much importance from the standpoint of the electronic conception of valence. 1955 B. C. L. KENT Elem. Org. Chem. (ed. 2) i. 21 The properties of CH2Cl.COOH will partly depend upon the presence of the carboxyl radical{em}COOH, partly upon the chloride radical{em}Cl, and partly upon the hydrocarbon residue (methylene) >CH2. 1982 G. C. HILL & J. S. HOLMAN Chem. in Context 144/1 Their effectiveness varied over a wide range depending on the hydrocarbon radicals attached to the nitrogen atom.

b. spec. = FREE RADICAL n.

1900 Jrnl. Amer. Chem. Soc. 22 768 The experimental evidence..forces me to the conclusion that we have to deal here with a free radical, triphenylmethyl... The radical so formed is apparently stable. 1933 Jrnl. Chem. Physics 1 369 In the first step the C – C bond breaks and there are formed two phenyl-methyl radicals. 1951 Jrnl. Amer. Chem. Soc. 73 5197/1 Chain termination occurs by combination of a polymer radical with either another polymer radical or an initiator radical. 1994 Sci. News 22 Oct. 260/3 A similar depletion of NOx in the stratosphere over Antarctica during the austral spring contributes to the efficiency with which chlorine radicals form.

Politics

Also with capital initial. A person who advocates radical or far-reaching political or social reform; a member of a political party or part of a party pursuing such aims. Now also: a (esp. left-wing) revolutionary. Also in extended use. Cf. radical reformer n. at Special uses 2.philosophical, Tory-, etc.: see at first element.

1802 in Spirit of Public Jrnls. (1803) 6 4 The sagacious only could have foreseen that he should have become a r{em}c{em}l. 1822 Cobbett's Weekly Polit. Reg. 30 Mar. 779 Love is a great leveller; a perfect Radical. 1822 J. Q. ADAMS Diary 16 June in Mem. J. Q. Adams (1875) VI. iii. 22 General Scott..said Archer was a Radical and inclined to be Jacobinical. 1847 Semi-Weekly News (Fredericksburgh, Va.) 21 Oct. 2/2 The Barnburners are the progressives, the radicals. 1876 San Francisco Daily Examiner 10 Oct. 2/1 The real issue with the Radicals is to divert public attention from the unexemplified corruption of the Radical party during the past eight years. 1888 W. H. DAWSON German Socialism i. 22 The association was joined by South German Radicals, North German students. 1921 N. Amer. Rev. Aug. 316 Liberals are merely terror-stricken Radicals. 1942 E. PAUL Narrow St. iv. 35 Some radical that year [sc. 1923] (they called them anarchists, not communists, then) had taken a pot shot at Léon Daudet. 1962 S. E. FINER Man on Horseback iv. 59 The Egyptian army officers were..right-wing radicals..with motivations much more akin to the Nazi storm-troopers. 1991 Economist 5-11 Jan. 41/2 So long as radicals were on the rampage, staying in the centre meant leaning ever further towards liberal reform.

b. Brit. A white hat affected by Radical supporters in the 19th cent. Cf. quot. 1841 at sense A. 7b. Obs. rare.

A white hat became popular among and characteristic of Radicals after Henry Hunt wore one at various political meetings in 1819-20. 1828 Lights & Shades Eng. Life I. 294 A whity-brown radical on his head, the edges of which are worn down to the brown-paper foundation.

Anatomy

RADICLE n. 3. 1880 V. D. HARRIS & D'A. POWER Man. Physiol. Lab. 54 The radicals of the hepatic vein. 1900 Philos. Trans. (Royal Soc.) B. 192 231 The attempt by Hamburger..to revive the filtration theory of absorption..compelled me to measure the hydrostatic pressure simultaneously in the gut lumen and in a radical of a mesenteric vein. 2002 M. BOWLES & M. RELA in P. S. Sidhu & G. M. Baxter Ultrasound Abdominal Transplantation III. 69/2 Biliary radicals drain into the right and left hepatic ducts which then form the common hepatic duct.

SPECIAL USES

S1. radical-minded adj.

1858 Times 30 Nov. 5/2 The following proposals will startle the most *radical-minded directeur or gérant. 1890 W. JAMES Princ. Psychol. I. 24 The more radical-minded reader can always read ‘ideational process’ for ‘idea’. 1907 W. DU BOIS in B. T. Washington Negro in South (Electronic text) iv. 137 Such condition stirred the more radical-minded toward abolition sentiments. 2006 Maclean's (Nexis) 12 June 32, I consider myself a politically moderate and non-violent person, but a philosophically radical-minded person.

radical protectionist adj. and n. 1866 Times 11 Jan. 8/4 There are powerful influences which may restrain the *Radical Protectionists from pushing their victory too far. 1905 Daily Chron. 30 June 6/2 It is reported that..a Radical-Protectionist Government will take office. 1930 Times 3 Dec. 14/6 He..soon became prominent among the Radical Protectionist section of Sir R. Banton's followers. 2006 Chattanooga (Tennassee) Times Free Press (Nexis) 22 Oct. F4 While radical protectionist measures have been rejected, Congress has balked at bigger steps to open international markets.

radical socialist adj. and n. 1862 N. Amer. Rev. Oct. 457 The *radical socialists who make right a creation of society. 1903 Ann. Reg. 1902 272 The Government remained in the hands of the bloc; and the Radical-Socialist party was free to proceed with the enforcement of the law with regard to the Congregations. 1908 Daily Chron. 6 Apr. 7/4 Under Mr. Asquith, the balance of power in the Government shifts from the Radical-Socialist to the more moderate Radical side. 1991 Profession 91 10/2 But to refuse to read Shakespeare, James Faulkner, and other so-called masters on radical socialist or feminist or cultural nationalist grounds is really another matter.

S2. radical axis n. [after French axe radical (L. Gaultier 1813, in Jrnl. de l'École Polytechnique 9 139)] Geom. the straight line which is the locus of the points whose powers (POWER n.1 12d) with respect to two given coplanar circles are equal.

1848 G. SALMON Treat. Conic Sections viii. 96 The line S - S' = O..has been called the *radical axis of the two circles. 1923 W. C. SWABEY & M. C. SWABEY tr. E. Cassirer Substance & Function (1953) iii. 84 In this case, also, there always exists a straight line,{em}the so-called ‘radical axis’ of the two circles,{em}which..can be called the ideal common chord of the two circles, which contains their two ‘imaginary’ points of intersection. 1992 H. EVES Fund. Mod. Elem. Geom. i. 44 The radical axes of three circles with noncollinear centers, taken in pairs, are concurrent.

radical centre n. [after French centre radical (L. Gaultier 1813, in Jrnl. de l'École Polytechnique 9 143)] Geom. (in a system of three coplanar circles) the point of intersection of the three radical axes of each of the three pairs of circles.

1848 G. SALMON Treat. Conic Sections viii. 97 Given any three circles, if we take the radical axis of each pair of circles, these three lines will meet in a point, and this point is called the *radical centre of the three circles. 1945 Amer. Math. Monthly 52 335 In a triangle ABC having altitudes AA´, BB´, CC´, the perpendiculars drawn from the midpoints of B´C´, C´A´, A´B´ to the sides BC, CA, AB respectively, are concurrent at the radical center of the circles..having centers A, B, C and radii AA´, BB´, CC´. 1951 Philos. Trans. (Royal Soc.) A. 244 41 The conics of the net N are ‘circles’ of which Q is the radical centre. 1989 E. J. BOROWSKI & J. M. BORWEIN Dict. Math. 485 Radical centre, (of three circles) the point of intersection of the respective radical axes of each pair of circles.

radical chic n. the fashionable affectation of radical left-wing views; the lifestyle or dress associated with this.

1970 S. KRIM Shake it for World, Smartass 186 The New Yorker..fluffed the challenge of imaginatively redefining its purpose..stretching its now rubber conscience to include tokens of *radical chic and impressiveness on top but not at the bottom where it counts. 1970 T. WOLFE in New York 8 June 40/2 Radical Chic invariably favors radicals who seem primitive, exotic, and romantic, such as the grape workers..the Panthers..and the Red Indians. 1973 Guardian 5 Mar. 20/4 (heading) For a taste of radical chic{em}try a plum jam buttie. 1995 Guardian 17 Oct. II. 3/1 Mr Smith has become a celebrity of radical chic Maoridom. 2006 Cineaste Summer 52/1 A prime example of radical chic that merits comparisons with the empty hipness of [a] Che T-Shirt.

radical circle n. [after French cercle radical (L. Gaultier 1813, in Jrnl. de l'École Polytechnique 9 131)] Geom. {dag}(a) (in a system of circles drawn on a sphere whose planes intersect in a common line) the circle whose plane passes through the centre of the sphere (obs.); (b) the circle whose centre is the radical centre of three given circles and which intersects each circle orthogonally.

1889 J. CASEY Spherical Trigonom. 101 The circle of the system S, whose plane passes through the centre of the sphere, is called the *radical circle of the system. 1927 Amer. Math. Monthly 34 357 The special cases are (1) O3c; (2) P1O2c; (3) P2Oc. The solution in each case is the radical circle. 1992 H. EVES Fund. Mod. Elem. Geom. 48 Show that if the radical center of three circles with noncollinear centers is exterior to each of the three circles, it is the center of a circle orthogonal to all three circles. (This circle is called the radical circle of the three circles.)

radical cure n. see sense A. 6.

adical empiricism n. Philos. (originally, in the philosophy of William James (1842-1910)) the theory that ultimate reality consists of pure experience; (more generally) the view that knowledge of reality can only be achieved through a rigorous and sceptical empiricism.

1897 W. JAMES Will to Believe p. vii, Were I obliged to give a short name to the attitude in question, I should call it that of radical empiricism... I say ‘empiricism’, because it is contented to regard its most assured conclusions concerning matters of fact as hypotheses liable to modification in the course of future experience; and I say ‘radical’, because it treats the doctrine of monism itself as an hypothesis. 1939 Philos. Sci. 6 343 The doctrine of radical empiricism that the entities into which scientific analysis involves phenomena must be directly and concretely (rather than indirectly and inferentially) observable. 1994 S. PINKER Lang. Instinct xiii. 427 Radical empiricism is not necessarily a progressive, humanitarian doctrine. A blank slate is a dictator's dream.

radical empiricist n. and adj. Philos. (a) n. an adherent or advocate of radical empiricism; (b) adj. of, relating to, or advocating radical empiricism.

1897 W. JAMES Will to Believe p. ix, This is pluralism, somewhat rhapsodically expressed. He who takes for his hypothesis the notion that it is the permanent form of the world is what I call a *radical empiricist. 1909 Philos. Rev. 18 536 The validity of the ‘radical empiricist’ attitude. 1973 K. B. MADSEN in D. Berlyne Pleasure, Reward, Preference xi. 286 We expect a radical empiricist to be a materialist rather than a dualist. 1995 Oxf. Compan. Philos. 425/1 James oscillates between various radical empiricist accounts of the physical world. 1999 Noûs 33 32, I gave three distinct self-defeat arguments showing that radical empiricists, who reject intuitions as evidence, end up with a self-defeating epistemology.

radical feminism n. advocacy of radical left-wing measures designed to counter the traditional dominance of men over women; the movement associated with this; (also) an instance of such advocacy.

[1913 Current Opinion Sept. 172/3 It is then that Fanny Hawthorn expresses her ultra-radical feminism and her simple theory of the economic independence of woman.] 1921 Cedar Rapids (Iowa) Evening Gaz. 7 Jan. [12]/3 It was not by any means a *radical feminism that they demonstrated. It was, rather, a conservative but common sense outlook. 1923 A. R. WADIA Ethics of Feminism i. 19 These would also have to be studied so as to enable us to judge how far they afford a stable basis for the advocates of radical feminism. 1991 M. MACKIE Gender Relations Canada viii. 201/1 The more recent political perspective of Radical Feminism argues that the oppression of women is the fundamental oppression. 2000 A. MORETON-ROBINSON Talkin' up to White Woman (2006) iv. 117 The focus of Bell's article was the appropriateness of radical feminism..for understanding and acting on male violence against women.

radical feminist adj. and n. (a) adj. reflecting or promoting radical feminism; (b) n. a supporter of radical feminism.

1905 Zion's Herald 22 Nov. 1476/1 The *radical feminists desire not to abolish marriage, but thoroughly reform it, revolting at the idea of the ‘domestic slavery’ which now oppresses so many women in all walks of life. 1971 S. FIRESTONE Dialectic of Sex ii. 16 In the radical feminist view, the new feminism is not just the revival of a serious political movement for social equality. 1994 Time 14 Feb. 55/2 John Stoltenberg, a radical feminist who wrote a book called The End of Manhood, divides men into misogynists and recovering misogynists. 2006 Toronto Sun (Nexis) 18 June C6 At times there seems to be a deep hatred for fatherhood, as demonstrated by irresponsible men who abandon their families, and some radical feminists (women and men) who proclaim fathers unnecessary.

radical ion n. Chem. a free radical species that carries a charge.

1963 Chem. Rev. 63 332/2 The fluorescence emission maxima are shifted to longer wavelengths..probably due to the formation of a *radical ion. 1977 J. MARCH Adv. Org. Chem. (ed. 2) xi. 508 Two principal mechanisms have been suggested, one involving cyclic attack by the oxygen of the nitro group..and the other involving a cleavage into a radical and a radical ion held together in a solvent cage. 2006 Tetrahedron 62 6457/1 The abundance of unusual pathways is perhaps the reason that radical ion chemistry is often viewed as being somewhat esoteric.

radical left n. people with extreme left-wing views; the side of the political spectrum occupied by these people; (in later use) spec. = NEW LEFT n.

1870 Times 22 Apr. 10/2 Government people are in high spirits at the accounts they receive from..the Chamber, now divided into the Parliamentary Left and the *Radical Left. 1876 Constitution 27 Jan. 3/1 He resolutely pushes the moderate left towards the radical left. 1965 E. WEBER in Rogger & Weber European Right 20 The violence and brutality of the radical Right became acceptable to conservatives who viewed them as defenders against the threat of a radical Left. 1994 Amer. Spectator Mar. 71/3 It is from Rousseau and his heirs that the radical left derives what might be described as its anarcho-Stalinist tendencies. 2002 R. COHEN By the Sword II. vii. 157 In November 1970 he marched into the Japanese Eastern Army headquarters and, railing to a demoralizingly indifferent crowd against both capitalism and the radical left, committed seppuku.

radical letter n. [compare post-classical Latin littera radicalis (1572 in the passage translated in quot. 1573 at sense A. 4a)] Linguistics (a) an original unchanged letter, esp. a Welsh initial consonant, which is liable to be altered or mutated by a preceding word; (b) a letter belonging to the root of a word, esp. one of the consonants of an Arabic or Hebrew root.

1573 *Radicale letter [see sense A. 4a]. 1609 H. CLAPHAM Chronol. Disc. xviii. sig. N3, Ram bam (that is, according to the 4. radicall letters, R. M. B. M. Rabbj Moses Ben Maymony). a1653 W. GOUGE Learned Comm. Heb. (1655) xi. 11. 41 Sarah hath all the radical letters in it. 1655 J. HOWELL 4th Vol. Familiar Lett. xix. 46 Wallia, which the Romans call'd Gallia, turning W into G.., yet the Walloon keeps his radical letter to this day. 1730 A. BEDFORD Script. Chronol. vi. 225/2 This Word [sc. Tros] contains all the radical letters of Tiras. 1769 T. LLEWELLYN Hist. & Crit. Remarks Brit. Tongue II. i. 60 The word in its first form is in its absolute state, and begins with its primary or radical letter. 1831 S. LEE Gram. Hebrew Lang. (1832) 222 One of the two last radical letters of any word, when both are the same, may..be rejected. 1955 R. H. RICHENS & A. D. BOOTH in Machine Transl. Langs. ii. 28 In Welsh, it may prove possible to have a single equivalent for p, ph, or mh, which are variants of the same radical letter. 1997 G. MAKDISI Ibn 'Aquil II. vii. 148 It is from the radical letters, JNN, that the fetus was called janin.

radical plane n. Geom. a plane whose points have equal power (POWER n.1 12d) with respect to two given spheres (identical with the plane containing the circle of intersection of the spheres if they intersect).

1872 Philos. Trans. 1871 (Royal Soc.) 161 652 The envelope of the *radical plane of a pair of inverse osculating spheres of a sphero-quartic is a cone of the fourth degree. 1961 C. C. T. BAKER Dict. Math. 253 If {lambda} is chosen as -1, this surface degenerates into the plane of intersection of the two spheres, and it is called the radical plane of the coaxal system. 2004 Computer-aided Design 36 1033/1 The radical plane of two spheres is the locus of the points for which the powers with respect to both spheres are equal.

radical pluralism n. a fundamental pluralism.

1904 W. JAMES in Jrnl. Philos., Psychol. & Sci. Methods 1 570 These are the main features of a philosophy of pure experience... In my own mind such a philosophy harmonizes best with a *radical pluralism. 1949 Mind 58 369, I remember well the dismay in an undergraduate philosophical society when one of the members..announced that he had adopted the ‘radical pluralism’ of this author [sc. Russell]. 2003 Polit. Theory 31 495 It is not clear why, in the face of radical pluralism, one would necessarily opt for satisfying as many goals as possible instead of pursuing a single goal.

radical pluralist n. and adj. (a) n. an adherent or advocate of a fundamental pluralism; (b) adj. of, relating to, or advocating a fundamental pluralism.

1911 W. JAMES Some Probl. Philos. x. 164 He concluded that such realities as present beings, past events and causes, steps of change and parts of matter, must needs exist in limited amount. This made of him a *radical pluralist. 1969 Amer. Polit. Sci. Rev. 63 943/1 Laski argued against the myth of the sovereign state, advancing instead a radical pluralist conception. 1986 Proc. & Addr. Amer. Philos. Assoc. 60 268 The radical or strict pluralists believe that philosophy does not exist; there are only philosophers. 2002 Polit. Theory 30 71 No attempt is made to wriggle out of the radical pluralist doctrine.

radical reform n. a thoroughgoing reform; spec. a reform of the British social and parliamentary system called for during the end of the 18th and early 19th cent. by those opposed to George III's parliamentary control.

1777 Parl. Reg. 1775-80 VII. 253 So far from expecting the African trade to flourish under the present laws and management, I am confident it cannot, without a complete *radical reform, much exist at all. 1798 Anti-Jacobin 5 Feb. 102/2 May success..lead..To one grand Radical Reform! 1815 tr. V. J. E. de Jouy Paris Chit-chat (1816) I. 54 Every body seems sensible of the necessity of radical reform both in politics and in manners. 1842 T. P. THOMPSON Exercises I. 227 The actual agent..will be a radical reform in what is called the commons house of parliament. 1996 U.S. News & World Rep. 3 June 42/1 The man who won office by championing radical reform has since..fired his liberal aides and now hopes to win reelection by more iron-fisted rule.

radical reformation n. = radical reform n.

1781 C. WYVILL Polit. Papers (1794) I. VI. viii. 341 While independent men, supported by large bodies of their fellow-citizens, have the virtue thus to resist corruption..the hope of a *radical reformation cannot be ill-founded. 1864 Times 8 Sept. 10/2, I cannot see any remedy except in such a radical reformation as the present state of things would hardly admit of. 2006 Los Angeles Times (Nexis) 29 Sept. B1 What we're about to undertake is a radical reformation of how healthcare is delivered in the southern part of Los Angeles.

radical reformer n. = sense B. 6.

1795 G. F. SYDNEY Hist. Catiline's Conspiracy 217 The class of politicians who think themselves qualified to be, in the modern phrase, *radical reformers of their country. 1819 SCOTT Let. 16 Oct. (1934) VI. 2 You will learn enough of the doings of the Radical Reformers from the papers. 1905 Times 19 Jan. 6/6 Mr. Samuel Storey said that he had been a Radical reformer all his life, and he came now to suggest two other reforms. 2006 Charleston (W. Va.) Gaz. (Nexis) 26 Oct. P4A Actually, the Nobel Prize-winning son was a radical reformer, the complete opposite of a Republican.

radical right n. (a) Sc. Law an owner's absolute or actual right in a piece of land or property, distinguished from another's equitable or trust rights in that property; (b) a political party or body of people with extreme conservative or fascist views favouring group action to protect or reinstate certain social traditions; the side of the political spectrum occupied by these people.

1714 W. FORBES Jrnl. Session 1705-13 345 The *radical Right of all the Product of the Ground is in the Master for his Rent. 1884 Law Rep.: Appeal Cases 9 312/2 The power of the granter to deal with her estate under the radical right is plain. 1927 N.Y. Times 27 Mar. E9/6 These youths and many thousands more like them are human clay from which the extremist politicians mold the cheap imitations of soldiers forming the militaristic organizations of the radical Right and Left. 1970 C. HAMPDEN-TURNER Radical Man (1971) ix. 267 This explains the relative efficiency and speed of organized groups on the Radical Right and the Communist Left. 2000 Session Cases 189 That radical right is of no value to the debtor unless the trustee eventually reconveys the property. 2003 N.Y. Rev. Bks. 12 June 26/1 The German radical right has found wellsprings of enduring resentment to exploit.

radical sign n. Math. the sign {sqrt} used to denote a root of the number or quantity to which it is prefixed.

Used by itself, {sqrt} indicates the square root; for the cube, fourth, etc., roots, appropriate numbers are added to give the signs 3{sqrt}, 4{sqrt}, etc.

For the history of the sign, see F. Cajori Hist. Math. Notations (1928) II. 366ff. The sign appears in a form similar to the modern one in Christoff Rudolff Behend unnd hubsch Rechnung durch die kunstreichen regeln Algebre, so gemeincklich die Coss genennt werden (1525), and in an English context in R. Record Whetstone of Witte (1557) sig. Ll.iij ff. 1668 tr. J. H. Rahn Introd. Algebra 43 In the quotient subjoyn the surd part with its first *radical Sign [Ger. unter sienem ersten zeichen dem rationalen]. 1679 J. MOXON Math. made Easy 173, {sqrt} A Radical Sign with an Index in it, signifies Evolution, as 2{sqrt}: A - B: Is the Square Root of A. less B. or, 3{sqrt}: A - B: is the Cube Root of A less B. a1746 C. MACLAURIN Treat. Algebra (1748) I. viii. 44 Placing above the radical Sign the Number that denominates what kind of Root is required. 1936 M. I. LOGSDON Mathematician Explains iii. 50 The roots given in the text are precise, and they cannot be given precisely without the use of a radical sign. 1997 D. K. BRUMBAUGH et al. Teaching Secondary Math. xiii. 350 A whole set of operations is available to deal with complex numbers. In the quadratic formula, the material beneath the radical sign is called the discriminant.

radical sound n. Linguistics (now rare) a sound belonging to the root of a word; an original, unchanged or indivisible sound; cf. radical letter n.

1754 D. FARROE Royal Universal Brit. Gram. & Vocab. I. i. 2 Letters are those Signs, Marks, or Characters which determine certain indivisible and *radical Sounds. 1833 W. GAMBOLD Welsh Gram. (ed. 3) iv. 13 After the prefix gor, the initials b, d, g, m, r, assume their Light sound; but after tra they retain their Radical sound; as gorfod,..trablin. 1845 J. O'DONOVAN Gram. Irish Lang. 39 Aspiration..of the Celtic..may be defined as the changing of the radical sounds of the consonants from being stops of the breath to a sibilance. 1919 Amer. Anthropologist 21 427 In ‘paternal uncle’ the radical sound is U of ‘father’ graded by the b{ibreve} suffix to convert it into uncle.

radical vinegar n. [compare French vinaigre radical (1765) and also earlier radicated vinegar n. at RADICATED adj. Special uses and later radicate vinegar n. at RADICATE adj. Special uses] Chem. (now arch. and hist.) = glacial acetic acid at GLACIAL adj. 2b (cf. radicated vinegar n. at RADICATED adj. Special uses).

?1766 W. SAUNDERS Syllabus Lect. Chymistry 9 Vinegar. Synonima..Acetous Acid. *Radical Vinegar. 1789 J. KEIR First Pt. Dict. Chem. 20/1 This acid is called radical vinegar, or spirit of Venus; which name is given by chemists to the acid of vinegar highly concentrated, obtained by distilling verdigrise. 1813 Pantologia (at cited word), The acid thus obtained..was formerly distinguished by the names of radical vinegar, and vinegar of Venus. 1966 J. S. COX Illustr. Dict. Hairdressing 124/2 Radical vinegar, glacial acetic acid.

radical word n. Linguistics a simple uncompounded word having the form of, or directly based on, a root.

1605 BACON Of Aduancem. Learning II. sig. Pp3v, They [sc. the Chinese] haue a vast multitude of Characters, as many (I suppose), as *Radicall words. 1642 J. HOWELL Instr. Forreine Travell x. 125 If one observe the Radicall words in that Language they are the same that are now spoken in Wales. 1777 J. RICHARDSON Diss. Eastern Nations 2 Radical words in any tongue are expressive of certain customs, objects and modes of thinking. 1865 Trans. Amer. Philos. Soc. 13 36 The publication of Bowen's Yoruba Grammar and Dictionary..has furnished to philologists a new and valuable Thesaurus of radical words. 1921 E. SAPIR Lang. ii. 29 Radical-words may and do occur in languages of all varieties. 2001 W. T. LYNCH Solomon's Child iv. 148 Every radical word in the tables refers to a noun substantive.

Reference

The Oxford English Dictionary (or the OED)