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actinost

noun
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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