The Collaborative International Dictionary of English v.0.48:

Syphon \Sy"phon\, n.
   See Syphon.
   [1913 Webster]

WordNet (r) 3.0 (2006):

syphon
    n 1: 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 [syn: siphon, syphon]
    2: a tubular organ in an aquatic animal (especially in mollusks)
       through which water can be taken in or expelled [syn:
       siphon, syphon]
    v 1: convey, draw off, or empty by or as if by a siphon [syn:
         siphon, syphon, siphon off]