noun ac·ti·nost \ˈak-tə-ˌnäst\

Definition of actinost



  1. :  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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Origin and Etymology of actinost

actin- + -ost

First Known Use: 1872

Seen and Heard

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a brief usually trivial fact

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