: having fleshy lobed fins : sarcopterygian
The coelacanth survives as the only known living member of a class of lobe-finned fishes that flourished in the Mesozoic Era …Lisa M. FitzGerald, Sea Frontiers, November/December 1992
But unlike other fish, lobe-finned fish aren't completely dependent on gills. They also have lungs with which they can breathe air …Carl Zimmer, Discover, June 1995
compare ray-finned
lobe-fin noun
plural lobe-fins

Word History

First Known Use

1896, in the meaning defined above

Time Traveler
The first known use of lobe-finned was in 1896

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Cite this Entry

“Lobe-finned.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lobe-finned. Accessed 24 Dec. 2025.

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