1.(Biol.) That which is to develop a new individual; as, the germ of a fetus, of a plant or flower, and the like; the earliest form under which an organism appears. "In the entire process in which a new being originates... two distinct classes of action participate; namely, the act of generation by which the germ is produced; and the act of development, by which that germ is evolved into the complete organism."
2.That from which anything springs; origin; first principle; as, the germ of civil liberty.
3.(Biol.) The germ cells, collectively, as distinguished from the somatic cells, or soma. Germ is often used in place of germinal to form phrases; as, germ area, germ disc, germ membrane, germ nucleus, germ sac, etc.
4.A microorganism, especially a disease-causing bacterium or virus; used informally, as, the don't eat food that falls on the floor, it may have germs on it.