porpoise

noun por·poise \ ˈpȯr-pəs \

|Updated on: 7 Jun 2018

Definition of porpoise

1 : any of a family (Phocoenidae) of small gregarious toothed whales; especially : a blunt-snouted usually dark gray whale (Phocoena phocoena) of the North Atlantic and North Pacific that typically ranges from 5 to 6 feet (1.5 to 1.8 meters) in length

2 : dolphin 1a(1) —not used technically

Note: While not closely related, porpoises and dolphins share a physical resemblance that often leads to misidentification. Porpoises typically have flat, spade-shaped teeth, triangular dorsal fins, and shortened beaks with relatively small mouths while dolphins have cone-shaped teeth, curved dorsal fins, and elongated beaks with larger mouths.

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Recent Examples of porpoise from the Web

Reidenberg examined 10 dead dolphins and porpoises that were stranded onshore to trace the connections between the mysterious blood vessels and the rest of the animals’ anatomies.

— matthew berger, Smithsonian, "Dolphins Have a Mysterious Network of Veins That Could Be Key to Preventing the Bends," 26 May 2018
Millar on March 3 was sailing off the coast of Bowen Island when he was instantly surrounded by Dall’s porpoises.

— Houston Chronicle, "Houston area sailing clubs and classes," 10 May 2018
The New England Aquarium said in a statement that a necropsy revealed the porpoise’s liver and other organs had been compromised by an unusually high number of parasites.

— laney ruckstuhl, BostonGlobe.com, "Pregnant porpoise dies on Dorchester Bay shore during the last nor’easter," 10 Mar. 2018
Ice isn't the only attraction on these boats: keep an eye out for whales and wildlife, puffins and porpoises, too.

— josh niva, Anchorage Daily News, "Getting your outdoor adventure fix in Southcentral Alaska," 2 May 2018
There's no guarantee the dolphin knocked him off on purpose (porpoise?).

— scott berson, miamiherald, "Paddleboarder praises dolphin who tackled him into the sea. 'Took me out quite well.' | Miami Herald," 1 May 2018
In 2004, the Ninth Circuit ruled that animals could have standing to sue, in a case involving whales, dolphins and porpoises allegedly harmed by Navy sonar.

— sara randazzo, WSJ, "Copyright Protection for Monkey Selfie Rejected by U.S. Appeals Court," 23 Apr. 2018
Fishing for totoaba involves gillnets that suffocate many different animals from birds to the nearly extinct vaquita porpoise.

— joshua emerson smith, sandiegouniontribune.com, "How we investigated wildlife trafficking," 22 Apr. 2018
The rugged stretch of coastline is regularly visited by whales, porpoises, and dolphins, and its northerly location means little light pollution (and lots of stars) at night.

— caitlin morton, Condé Nast Traveler, "The Most Beautiful Places in Ireland," 16 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'porpoise.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of porpoise

Middle English porpoys, from Anglo-French porpeis, from Medieval Latin porcopiscis, from Latin porcus pig + piscis fish — more at farrow, fish

NEW! Time Traveler

First Known Use: 14th century

in the meaning defined at sense 1

See Words from the same year