por·​poise | \ ˈpȯr-pəs How to pronounce porpoise (audio) \

Definition of porpoise

 (Entry 1 of 2)

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 sense 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.


porpoised; porpoising; porpoises

Definition of porpoise (Entry 2 of 2)

intransitive verb

1 : to leap or plunge like a porpoise penguins … porpoise out of the water— David Lewis
2 : to rise and fall repeatedly

Examples of porpoise in a Sentence

Recent Examples on the Web: Noun If the vaquita is protected and the gillnet deaths stop completely, the team estimated that there would only be a 6 percent chance that the porpoise would go extinct in half a century, NPR reports. Elizabeth Gamillo, Smithsonian Magazine, 11 May 2022 The vaquita porpoise has become more resilient to inbreeding and can avoid harmful genetic mutations, as a result of living in relatively small population sizes, according to the study. Camille Fine, USA TODAY, 10 May 2022 With only around 10 individuals left in the world, a tiny porpoise called the vaquita is facing extinction. Doug Johnson, Ars Technica, 6 May 2022 But that may not yet spell doom for the vaquita porpoise, according to new research. Ashley Strickland, CNN, 5 May 2022 It was designed to be easily employed as well, launching directly from the surface and re-emerge from under ground upon completion, like a porpoise, according to the company. Christiaan Hetzner, Fortune, 25 Apr. 2022 Today Kwame Kilpatrick; saving the world’s rarest porpoise; Makho Ndlovu; Geoffrey Zakarian. Matt Cooperlistings Coordinator, Los Angeles Times, 21 Apr. 2022 Then there’s the vaquita, an even more endangered species of small harbor porpoise, caught as collateral damage in nets set out for totoaba. Washington Post, 5 Apr. 2022 Whenever a porpoise or dolphin or whale washed up on a Northern California shoreline, Izzy Szczepaniak was usually the first on the scene. Sam Whiting, San Francisco Chronicle, 9 Dec. 2021 Recent Examples on the Web: Verb Calvin stepped up to the glass, watching Fiona porpoise around Hippo Cove with her mother, Bibi. Mallorie Sullivan, Cincinnati.com, 20 Feb. 2018 See More

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.

First Known Use of porpoise


14th century, in the meaning defined at sense 1


1909, in the meaning defined at sense 1

History and Etymology for porpoise


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

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The first known use of porpoise was in the 14th century

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Dictionary Entries Near porpoise



porpoise oil

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Last Updated

16 May 2022

Cite this Entry

“Porpoise.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porpoise. Accessed 18 May. 2022.

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More Definitions for porpoise


por·​poise | \ ˈpȯr-pəs How to pronounce porpoise (audio) \

Kids Definition of porpoise

1 : a small whale with teeth that resembles a dolphin but has a blunt rounded snout

More from Merriam-Webster on porpoise

Nglish: Translation of porpoise for Spanish Speakers

Britannica.com: Encyclopedia article about porpoise


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