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.(noun)
source: webster1913
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.(noun)