plural noun

in many classifications
: a superorder or other category of teleost fishes containing originally all those having the anterior rays of the dorsal and anal fins stiff and spiny (as the basses, perches, and mackerels) or now those usually lacking a duct to the air bladder, having no mesocoracoid bone, and having the pectoral arch suspended from the skull, the ventral fins attached to the clavicular arch, and the gill opening in front of the pectoral fin (as most of the spiny-finned and some soft-finned fishes)

Word History


New Latin, from acanth- + -pterygii (from Greek pterygion fin, small wing)

First Known Use

1751, in the meaning defined above

Time Traveler
The first known use of Acanthopterygii was in 1751

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Dictionary Entries Near Acanthopterygii

Cite this Entry

“Acanthopterygii.” Dictionary, Merriam-Webster, Accessed 19 Apr. 2024.

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