Source : Webster's Revised Unabridged Dictionary (1913)

Coptic \Cop"tic\ (k[o^]p"t[i^]k), a. [Abbrev. from L. Aegyptius
   an Egyptian, Gr. ?, Ar. kibt[=i], pl. kibt.]
   Of or pertaining to the Copts. -- n. The language of the
   Copts.

Source : WordNet®

Coptic
     adj : of or relating to the Copts or their church or language or
           art; "the distinctive Coptic art of 6th-century
           Christian Egypt"

Coptic
     n : the liturgical language of the Coptic Church used in Egypt
         and Ethiopia; written in the Greek alphabet