Definify.com
Webster 1913 Edition
Ischial
Is′chi-al
(ĭs′kĭ-al)
, Adj.
(Anat.)
Of or pertaining to the ischium or hip; ischiac; ischiadic; ischiatic.
Ischial callosity
(Zool.)
, one of the patches of thickened, hairless, and often bright-colored skin, on the buttocks of many apes, as the drill.