\Hyp"o*gene\, a. [Pref. hypo- + the root of Gr. ? to be
born: cf. F. hypog[`e]ne.] (Geol.)
Formed or crystallized at depths the earth's surface; -- said
of granite, gneiss, and other rocks, whose crystallization is
believed of have taken place beneath a great thickness of
overlying rocks. Opposed to epigene.