The Collaborative International Dictionary
Ischion
Ischion \Is"chi*on\, Ischium \Is"chi*um\, n. [L., Gr. 'ischi`on.]
(Anat.) The ventral and posterior of the three principal bones composing either half of the pelvis; seat bone; the huckle bone.
(Zo["o]l.) One of the pleur[ae] of insects.