1. (Science: biology) That which is to develop a new individual; as, the germ of a foetus, 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. (Carpenter)
(Science: biology) disease germ, the theory that living organisms can be produced only by the evolution or development of living germs or seeds. See biogenesis, and abiogenesis. As applied to the origin of disease, the theory claims that the zymotic diseases are due to the rapid development and multiplication of various bacteria, the germs or spores of which are either contained in the organism itself, or transferred through the air or water. See fermentation theory.