1. (noun)siphon, syphon a tube running from the liquid in a vessel to a lower level outside the vessel so that atmospheric pressure forces the liquid through the tube Synonyms: syphon, siphon
2. (verb)siphon, syphon a tubular organ in an aquatic animal (especially in mollusks) through which water can be taken in or expelled Synonyms: syphon, siphon
3. (verb)siphon, syphon, siphon off convey, draw off, or empty by or as if by a siphon Synonyms: syphon, siphon off, siphon