inequilateral

from The Collaborative International Dictionary of English v.0.48
Inequilateral \In*e`qui*lat"er*al\, a.
   1. Having unequal sides; unsymmetrical; unequal-sided.
      [1913 Webster]

   2. (Zool.) Having the two ends unequal, as in the clam,
      quahaug, and most lamellibranch shells.
      [1913 Webster]
    

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