资料来源 : pyDict

两面凹的

资料来源 : Webster's Revised Unabridged Dictionary (1913)

Biconcave \Bi*con"cave\, a. [Pref. bi- + concave.]
   Concave on both sides; as, biconcave vertebr[ae].

资料来源 : WordNet®

biconcave
     adj : concave on both sides [syn: {concavo-concave}]