\Pro"to*plast\, n. [L. protoplastus the first man, Gr. ? formed or created first; ? first + ? formed, fr. ? to form.] 1. The thing first formed; that of which there are subsequent copies or reproductions; the original. 2. (Biol.) A first-formed organized body; the first individual, or pair of individuals, of a species. A species is a class of individuals, each of which is hypothetically considered to be the descendant of the same protoplast, or of the same pair of protoplasts. --Latham.