Meaning of authigenic

au•thi•gen•ic

Pronunciation: (ô"thi-jen'ik), [key]
— adj. Geol.
  1. (of a constituent of a rock) formed in the rock where it is found. Cf. allogenic (def. 1).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.