Origin: 1935–40; < NL; L: the action of conceiving, hence, something that is conceived, fetus, embryo, equiv. to concep- (var. s. of concipere to conceive; see concept) + -tus suffix of v. action
con·cep·tus (kən-sěp'təs) n. The product of conception at any point between fertilization and birth. It includes the embryo or the fetus as well as the extraembryonic membranes.