The Collaborative International Dictionary of English v.0.48:
Rugose \Ru*gose"\, a. [L. rugosus, r. ruga a wrinkle.] Wrinkled; full of wrinkles; specifically (Bot.), having the veinlets sunken and the spaces between them elevated, as the leaves of the sage and horehound. [1913 Webster]WordNet (r) 3.0 (2006):
rugose adj 1: of leaves; ridged or wrinkled