What is pertaining to the segment between the basibranchial and the ceratobranchial in a branchial arch. -- n. A hypobranchial bone or cartilage called?

hypobranchial — Pertaining to the segment between the basibranchial and the ceratobranchial in a branchial arch. -- n. A hypobranchial bone or cartilage. (Webster's 1913.)

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