Hypogene \Hyp"o*gene\, a. [Pref. hypo- + the root of Gr. ? to be
born: cf. F. hypog[`e]ne.] (Geol.)
Formed or crystallized at depths beneath 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}.
[1913 Webster]