surangular

from The Century Dictionary.

• In zoology, noting one of the several bones of the compound mandible or lower jaw of birds, reptiles, etc., situated over the angular bone, near the angle or proximal end of the series. Also supra-angular. Also, as a noun, this bone itself. See cut under Gallinæ.
• noun A bone which takes part in the formation of each ramus of the lower jaw, lying on the outer side of the upper, posterior part of the jaw. It is found in vertebrates below mammals.

from the GNU version of the Collaborative International Dictionary of English.

• adjective (Anat.) Above the angular bone; supra-angular; -- applied to a bone of the lower jaw in many reptiles and birds.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective anatomy Above the angular bone; supra-angular
• noun anatomy A bone of the lower jaw in many reptiles and birds.