‖n. pl. [ NL.; Gr. fy^kos seaweed + mycetes. ] (Bot.) A large, important class of parasitic or saprophytic fungi, the algal or algalike fungi. The plant body ranges from an undifferentiated mass of protoplasm to a well-developed and much-branched mycelium. Reproduction is mainly sexual, by the formation of conidia or sporangia; but the group shows every form of transition from this method through simple conjugation to perfect sexual reproduction by egg and sperm in the higher forms. -- Phy`co*my*ce"tous a. [Webster 1913 Suppl.]