Source : Webster's Revised Unabridged Dictionary (1913)

Theologian \The`o*lo"gi*an\, n. [Cf. F. th['e]ologien, L.
   theologus, Gr. ?. See {Theology}.]
   A person well versed in theology; a professor of theology or
   divinity; a divine.

Source : WordNet®

theologian
     n : someone who is learned in theology or who speculates about
         theology (especially Christian theology) [syn: {theologist},
          {theologizer}, {theologiser}]