pectoral fin

American  

noun

1. (in fishes) either of a pair of fins usually situated behind the head, one on each side, and corresponding to the forelimbs of higher vertebrates.

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pectoral fin British  

noun

1. either of a pair of fins, situated just behind the head in fishes, that help to control the direction of movement during locomotion

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Etymology

Origin of pectoral fin

First recorded in 1760–70

Example Sentences

Her giant head and white pectoral fins - fringed with barnacles - are visible as she slowly floats beneath us.

From BBC

UC Riverside researchers discovered that some sharks responded to the heat with elongated pectoral fins.

From Science Daily

Fossils were meticulously prepared to remove the surrounding matrix of rock and expose the skull, shoulder girdle and pectoral fins.

From Science Daily

But on Thursday, the whale breached for about 40 minutes, also performing several pectoral fin slaps and dives.

From Seattle Times

Their pectoral fins are the largest of any whale, nearly a third as long as their body.

From Seattle Times