Source : Webster's Revised Unabridged Dictionary (1913)

Tor \Tor\, n. [AS. torr; cf. Gael. torr. Cf. {Tower}.]
   1. A tower; a turret. [R.] --Ray.

   2. High-pointed hill; a rocky pinnacle. [Prov. Eng.]

            A rolling range of dreary moors, unbroken by tor or
            tree.                                 --C. Kingsley.

Source : WordNet®

tor
     n 1: a prominent rock or pile of rocks on a hill
     2: a high rocky hill