Thoracostei

plural noun

Tho·​ra·​cos·​tei

ˌthōrəˈkästēˌī,

ˌthȯr-

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

Etymology

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

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