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actinost

noun
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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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Time Traveler for actinost

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The first known use of actinost was in 1872

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Dictionary Entries Near actinost

Actinosphaerium

actinost

actinostele

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Cite this Entry

“Actinost.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinost. Accessed 19 Oct. 2021.

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