Ep'i-gēne, a.

a. [Gr. ἐπιγενής, growing upon, from ἐπί, upon, and γίγνεσθαι, to begin to be, to be born, to grow.]

1. (Crystallog.) Foreign; unnatural; unusual; —said of forms of crystals not natural to the substances in which they are found.
2. (Geol.) Formed or originating on the surface of the earth; —opposed to hypogene; as, epigene rocks.