plural noun

in some classifications
: an order comprising fishes with the body more or less completely covered by bony plates and the pharyngeal bones and other structures about the head more or less undeveloped and including the sticklebacks, pipefishes, and sea horses

Word History


New Latin, from thorac- + -ostei (from Greek osteon bone)

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Dictionary Entries Near Thoracostei

Cite this Entry

“Thoracostei.” Dictionary, Merriam-Webster, Accessed 25 Jun. 2024.

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