pectoral fin

noun

: either of the fins of a fish that correspond to the forelimbs of a quadruped

Examples of pectoral fin in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Male zebrafish develop special structures on their pectoral fins that help with reproduction. — Junsu Kang, The Conversation, 5 Oct. 2026 Real manta rays propel themselves by rhythmically flapping and undulating their enormous pectoral fins. — New Atlas, 8 Sep. 2026 The three belugas that traveled to San Diego on Saturday were each placed on padded stretchers that featured small holes for their pectoral fins. — Lori Weisberg, San Diego Union-Tribune, 22 Aug. 2026 First, an orca will target the pectoral fins, then slash the sunfish across its body to remove the viscera. — Jennifer Ouellette, ArsTechnica, 23 July 2026 See All Example Sentences for pectoral fin

Word History

First Known Use

1715, in the meaning defined above

Time Traveler
The first known use of pectoral fin was in 1715

Rhymes for pectoral fin

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Browse Nearby Words

pectoral cross
pectoral fin
pectoral girdle
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Cite this Entry

“Pectoral fin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pectoral%20fin. Accessed 14 Oct. 2026.

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Kids Definition

pectoral fin

noun
: either of a pair of fins of a fish that correspond to the front limbs of a four-footed animal compare pelvic fin

More from Merriam-Webster on pectoral fin

Britannica.com: Encyclopedia article about pectoral fin

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