The Collaborative International Dictionary of English v.0.48:

Oryza \O*ry"za\, prop. n. [L., rice, Gr. ? See Rice.] (Bot.)
   A genus of grasses including the rice plant; rice.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Oryza
    n 1: rice [syn: Oryza, genus Oryza]