Source : WordNet®

dorsa
     See {dorsum}

dorsum
     n 1: the posterior part of a human (or animal) body from the neck
          to the end of the spine; "his back was nicely tanned"
          [syn: {back}]
     2: the back of the body of a vertebrate or any analogous
        surface (as the upper or outer surface of an organ or
        appendage or part); "the dorsum of the foot"
     [also: {dorsa} (pl)]