ray-finned

adjective

: 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

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