ischium

is·chi·um

noun \ˈis-kē-əm\

plural ; is·chia \-ə\ (audio pronunciation)

Definition of ISCHIUM

: the dorsal and posterior of the three principal bones composing either half of the pelvis consisting in humans of a thick portion, a large rough eminence on which the body rests when sitting, and a forwardly directed ramus which joins that of the pubis

Illustration of ISCHIUM