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adipose fin

American  

noun

  1. a small, fleshy fin, usually lacking rays, behind the main dorsal fin in trouts, catfishes, and other bony fishes.

adipose fin British  

noun

  1. a posterior dorsal fin occurring in some fish, such as those of the salmon and catfish families

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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.