Of a fetus: alive; spec. that has reached the stage of quickening (quickening, n.1 1b). Chiefly in with (also †mid) quick child.

†(a) designating a type of atavism characterized by the persistence or development of an early embryonic structure which would normally disappear (obs…

Embryology. Of, relating to, or characterized by a mode of development in which regions in an embryo are predetermined by the corresponding regions…

Biology. Of or relating to an anlage. Cf. proton, n. 1. disused.

Not yet viable; occurring or existing before the stage when a fetus has developed sufficiently to survive outside the uterus.

Embryology. Of, pertaining to, or producing induction (sense 9d).