syconPronunciation: /ˈsʌɪkɒn/Definition of sycon noun Zoology a sponge of a grade of structure showing some folding of the body wall, with choanocytes only lining radial canals. Compare with ascon and leucon.Derivatives syconoid adjective Origin: late 19th century: adopted as a genus name from Greek sukon 'fig'sycon in other Oxford dictionaries Definition of sycon in the US English dictionary