Sarcopterygii

plural noun

Sar·​cop·​te·​ryg·​ii ˌsär-ˌkäp-tə-ˈri-jē-ˌī 

: a subclass or other division of bony fishes (such as the coelacanth) that have paired, lobed, fleshy fins somewhat resembling limbs, that may be ancestral to the terrestrial vertebrates, and that have existed since the Devonian but are now largely extinct compare actinopterygii

Word History

First Known Use

1962, in the meaning defined above

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