Source : Webster's Revised Unabridged Dictionary (1913)

Deformation \Def`or*ma"tion\, n. [L. deformatio: cf. F.
   d['e]formation.]
   1. The act of deforming, or state of anything deformed. --Bp.
      Hall.

   2. Transformation; change of shape.

Source : WordNet®

deformation
     n 1: a change for the worse [syn: {distortion}]
     2: alteration in the shape or dimensions of an object as a
        result of the application of stress to it
     3: the act of twisting or deforming the shape of something
        (e.g., yourself) [syn: {contortion}]