Definition of crossopterygian
: any of a subclass (Crossopterygii) of bony fishes (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
Origin of 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
First Known Use: 1861
Learn More about crossopterygian
Britannica.com: Encyclopedia article about "crossopterygian"
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