reniform

from WordNet (r) 3.0 (2006)

reniform
    adj 1: (of a leaf or bean shape) resembling the shape of kidney
           [syn: {reniform}, {kidney-shaped}]

from The Collaborative International Dictionary of English v.0.48

Reniform \Ren"i*form\ (r?n"?-f?rm; 277), a. [L. renes kidneys +
   -form: cf. F. r['e]niforme.]
   Having the form or shape of a kidney; as, a reniform mineral;
   a reniform leaf.
   [1913 Webster] Renitence