Noun | 1. | ![]() fungus - an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytia family Lycoperdaceae, Lycoperdaceae - a fungus family belonging to the order Lycoperdales; includes puffballs Calvatia gigantea, giant puffball - huge edible puffball up to 2 feet diameter and 25 pounds in weight |