The Collaborative International Dictionary of English v.0.48:

Cordate \Cordate\ (k[^o]r"d[asl]t), a. [L. cor, cordis, heart.]
   (Bot.)
   Heart-shaped; as, a cordate leaf.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cordate
    adj 1: (of a leaf) shaped like a heart [syn: cordate, heart-
           shaped, cordiform]