plural noun

: 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


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

Time Traveler
The first known use of Actinistia was in 1871

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Dictionary Entries Near Actinistia

Cite this Entry

“Actinistia.” Dictionary, Merriam-Webster, Accessed 28 May. 2024.

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