actinost

noun

ac·​ti·​nost

ˈak-tə-ˌnäst

plural -s

: one of certain small bones directly supporting the rays of paired fins of teleost and some ganoid fishes

called also carpal, pterygiophore

compare hypercoracoid

Word History

Etymology

actin- + -ost

First Known Use

1872, in the meaning defined above

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