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


actin- + -ost

First Known Use

1872, in the meaning defined above

Time Traveler
The first known use of actinost was in 1872

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Dictionary Entries Near actinost

Cite this Entry

“Actinost.” Dictionary, Merriam-Webster, Accessed 14 Jul. 2024.

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