cros·​sop·​ter·​yg·​ian | \ ˌkrȯ-ˌsäp-tə-ˈri-j(ē-)ən How to pronounce crossopterygian (audio) \

Definition of crossopterygian

: any of a subclass (Crossopterygii) of bony fishes (such as a coelacanth) that have paired fins suggesting limbs, that may be ancestral to the terrestrial vertebrates, and that are mostly extinct

called also lobe-fin

Other Words from crossopterygian

crossopterygian adjective

First Known Use of crossopterygian

1861, in the meaning defined above

History and Etymology for crossopterygian

New Latin Crossopterygii, subclass name, from Greek krossoi fringe + pterygion, diminutive of pteryg-, pteryx wing, fin; akin to Greek pteron wing — more at feather

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The first known use of crossopterygian was in 1861

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Cite this Entry

“Crossopterygian.” The Dictionary, Merriam-Webster Inc., Accessed 28 January 2020.

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showing steady, earnest care and effort

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