Source : Webster's Revised Unabridged Dictionary (1913)

Eozoic \E`o*zo"ic\, a. [See {Eozo["o]n}.] (Geol.)
   Of or pertaining to rocks or strata older than the Paleozoic,
   in many of which the eozo["o]n has been found.

   Note: This term has been proposed for the strata formerly
         called Azoic, and is preferred especially by those
         geologists who regard the eozo["o]n as of organic
         origin. See {Arch[ae]an}.