ceratobranchial

from The Century Dictionary.

• Noting the principal and median piece of a branchial arch in fishes.
• noun In Owen's nomenclature of the parts of a hyoid bone, that bone which, in vertebrates below mammals, is borne upon the end of the hypobranchial, and, in a bird for instance, forms the terminal portion of the greater cornu of the hyoid, the hypobranchial and ceratobranchial together forming the so-called thyrohyal, which curves up behind the skull.
• noun In later nomenclature, same as the apohyal of some authors and the hypobranchial of Owen.

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

• adjective (Anat.) Pertaining to the bone, or cartilage, below the epibranchial in a branchial arch.

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

• adjective anatomy Relating to the bone or cartilage below the epibranchial in a branchial arch.
• noun anatomy A ceratobranchial bone or cartilage.