I. ˈsfē-ˌnȯid adjective
or sphe·noi·dal sfi-ˈnȯi-d ə l
Etymology: New Latin sphenoides, from Greek sphēnoeidēs wedge-shaped, from sphēn wedge
Date: 1732
1. : of, relating to, or being a winged compound bone of the base of the cranium
2. usually sphenoidal : having a wedged shape
II. noun
Date: 1828
: a sphenoid bone