Source : Webster's Revised Unabridged Dictionary (1913)

Biconvex \Bi*con"vex\, a. [Pref. bi- + convex.]
   Convex on both sides; as, a biconvex lens.

Source : WordNet®

biconvex
     adj : convex on both sides; lentil-shaped [syn: {convexo-convex},
           {lenticular}, {lentiform}]