mid-15c., "bud, sprout;" 1640s, "rudiment of a new organism in an existing one," from Middle French germe "germ (of egg); bud, seed, fruit; offering," from Latin germen (genitive germinis) "sprout, bud," perhaps from PIE root *gen- "to beget, bear" (see genus). The older sense is preserved in wheat germ and germ of an idea; sense of "seed of a disease" first recorded 1803; that of "harmful microorganism" dates from 1871. Germ warfare recorded from 1920.
germ (jûrm)
n.
A small mass of protoplasm or cells from which a new organism or one of its parts may develop.
A microorganism, especially a pathogen.