ac·​ti·​nost | \ ˈak-tə-ˌnäst \
plural -s

Definition of actinost

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

called also carpal, pterygiophore

— compare hypercoracoid

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First Known Use of actinost

1872, in the meaning defined above

History and Etymology for actinost

actin- + -ost

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The first known use of actinost was in 1872

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Cite this Entry

“Actinost.” Dictionary, Merriam-Webster, Accessed 20 Oct. 2020.

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