Siphon
Origin
French siphon, from Latin siphon-, sipho tube, pipe, siphon, from Greek siphōn
Definitions
- 1a : a tube bent to form two legs of unequal length by which a liquid can be transferred to a lower level over an intermediate elevation by the pressure of the atmosphere in forcing the liquid up the shorter branch of the tube immersed in it while the excess of weight of the liquid in the longer branch when once filled causes a continuous flow
- b usually syphon : a bottle for holding aerated water that is driven out through a bent tube in its neck by the pressure of the gas when a valve in the tube is opened
- 2: any of various tubular organs in animals and especially mollusks or arthropods that are used for drawing in or ejecting fluids.
Description
The word siphon (Greek: Σίφων, also spelled syphon) is sometimes used to refer to a wide variety of devices that involve the flow of liquids through tubes. But in the English language today, the word siphon usually refers to a tube in an inverted U shape which causes a liquid to flow uphill, above the surface of the reservoir, without pumps, powered by the fall of the liquid as it flows down the tube under the pull of gravity, and is discharged at a level lower than the surface of the reservoir. In practical siphons, atmospheric pressure pushes the liquid up the tube into the region of reduced pressure at the top of the tube. The reduced pressure is caused by liquid falling on the exit side. In the laboratory, some siphons have been demonstrated to work in a vacuum, indicating the tensile strength of the liquid is contributing to the operation of siphons at very low pressures.
