1Any of several types of reproductive structure in invertebrates; especially a part of the body from which new individuals arise asexually, usually by budding (now disused).
2A supply of genetic material; a gene pool.
Origin
Mid 19th century.
Definition of germ stock in US English:
germ stock
noun
1Any of several types of reproductive structure in invertebrates; especially a part of the body from which new individuals arise asexually, usually by budding (now disused).