Actinistia

plural noun

Ac·​ti·​nis·​tia

ˌak-tə-ˈni-stē-ə

: an order (superorder Crossopterygii) of chiefly Mesozoic fishes including the family Coelacanthidae having the interspinous bones supporting each dorsal and anal fin fused into one piece compare latimeria

Word History

Etymology

New Latin, from actin- + -istia (from Greek histion web, cloth, sail); akin to Greek histos mast, weaver's beam, web

First Known Use

1871, in the meaning defined above

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