The Collaborative International Dictionary
Ischial
Ischial \Is"chi*al\ ([i^]s"k[i^]*al), a. (Anat.) Of or pertaining to the ischium or hip; ischiac; ischiadic; ischiatic.
Ischial callosity (Zo["o]l.), one of the patches of thickened, hairless, and often bright-colored skin, on the buttocks of many apes, as the drill.
Wiktionary
ischial
a. Pertaining to the ischium. (from 19th c.)
WordNet
Wikipedia
Usage examples of "ischial".
She beckoned to one of the creatures, a thing with long silken hair and garishly colored ischial callosities that resembled a cross between a dwarf mastodon and a mandrill baboon.