1 (mycol.) A thick-walled, asexually derived spore formed from a portion of a vegetative hypha.
2 (bryol.) A structure formed by certain mosses and liverworts, which functions in vegetative reproduction (see vegetative propagation). Gemmae may consist of 1, 2, or many cells. See also Marchantia; Lunularia; and Tetraphidales.
3 A vegetative propagule that is a modified organ of the parent plant (e.g. the small lateral bulbils of Agave americana, the century plant).