noun.
In botany and zoology, a bud; that which is budded; the result of gemmation.
noun.
[capitalized] In conchology, a genus of bivalve mollusks, of the family Veneridæ, containing a single small species, G. totteni or G.gemma (originally Venus gemma), about one eighth of an inch long, yellowish or rosy-white tipped with amethystine, found on the Atlantic coast of the United States. The young are retained inside the valves of the parent till their shells are formed.
noun.
In biology, one of the hypothetical units of living matter: similar to biogen, idioblast, pangen, plasome, etc.
noun.
A knoblike protuberance or nodule.