: having fins supported by bony or horny rays (see ray entry 2 sense 5a(1)) : acanthopterygian
The vast majority of ray-finned fish species are contained in the Teleostei, a clade noted for its diversity of behavior, functional morphology, and ecology in aquatic habitats throughout the world.George V. Lauder, Quarterly Review of Biology, March 1999
Morays belong to a group called ray-finned fishes that includes a vast majority of fish species, like tuna, goldfish, salmon and trout.Carl Zimmer, New York Times, 11 Sept. 2007
compare lobe-finned
ray-fin noun
plural ray-fins
All the fossils belonging to the ancestral group that gave rise to ray-fins some 300 million years ago came from freshwater deposits. Colin Barras, New Scientist, 11 Feb. 2012

Word History

First Known Use

1933, in the meaning defined above

Time Traveler
The first known use of ray-finned was in 1933

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Dictionary Entries Near ray-finned

Cite this Entry

“Ray-finned.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ray-finned. Accessed 16 Jul. 2024.

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