Source : Webster's Revised Unabridged Dictionary (1913)

Heterodoxy \Het"er*o*dox`y\, n. [Gr. ?: cf. F.
   h['e]t['e]rodoxie.]
   An opinion or doctrine, or a system of doctrines, contrary to
   some established standard of faith, as the Scriptures, the
   creed or standards of a church, etc.; heresy. --Bp. Bull.

Source : WordNet®

heterodoxy
     n 1: any opinions or doctrines at variance with the official or
          orthodox position [syn: {unorthodoxy}, {heresy}] [ant: {orthodoxy}]
     2: the quality of being unorthodox [syn: {unorthodoxy}] [ant: {orthodoxy}]