The Collaborative International Dictionary of English v.0.48:

Anisometric \An`i*so*met"ric\, a. [Gr. 'an priv. + E.
   isometric.]
   Not isometric; having unsymmetrical parts; -- said of
   crystals with three unequal axes. --Dana.
   [1913 Webster]

WordNet (r) 3.0 (2006):

anisometric
    adj 1: having unsymmetrical parts or unequal dimensions or
           measurements [syn: anisometric, unsymmetrical]