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 While other marine reptiles such as porpoise-like ichthyosaurs and long-necked plesiosaurs had the evolutionary flexibility to expand into deeper ocean environments, hyper-specialized thalattosaurs like Gunakadeit may have struggled to follow suit. Katherine J. Wu, Smithsonian Magazine, "215-Million-Year-Old, Sharp-Nosed Sea Creature Was Among the Last of Its Kind," 5 Mar. 2020 Dubbed the unicorn of the sea due to their long, spiraled tooth, narwhals are a beloved Arctic animal that, like other porpoise species, can be spotted swimming in groups of dozens or even hundreds of animals. National Geographic, "Penguins don't live at the South Pole, and more polar myths debunked," 3 Feb. 2020 The second daughter, 54-year-old Celia, is a marine biologist and now works at the Havana Seaquarium specializing in seals and porpoises. Lisette Poole, Smithsonian, "Roaring Through Cuba With Che Guevara’s Son," 24 Oct. 2019 The Crown also lays claim to all unmarked swans in open waters, a decree dating to a time when swan meat was coveted, and all whales, sturgeon, and porpoises within 3 miles of the U.K. shoreline. TheWeek, "How the Royals get their money," 2 Feb. 2020 Vaquitas, which are the smallest porpoises in the world, have fallen to the razor’s edge of extinction, with about 10 remaining individuals—but last month, scientists glimpsed mothers with calves in the Gulf of California. National Geographic, "Wildlife wins: 7 good-news stories from 2019," 20 Dec. 2019 In fact, as Karin Bruillard at the Washington Post reports, the porpoises were seen as far upriver as Alexandria, Virginia, in the 1840s. Jason Daley, Smithsonian, "Dolphins Are Finally Living and Breeding in the Potomac River Again," 2 Oct. 2019 Just a two-hour flight from Seattle, the Inside Passage boasts majestic humpback whales, playful porpoises, soaring bald eagles and mighty grizzly bears. Sunset Magazine, "Sail the Seas of the Inside Passage to Witness Seven Natural Wonders," 22 Jan. 2018 During one outing, Corbett found a group of three killer whales chasing a pod of 15 porpoises (which also eat salmon). Alex Robinson, Outdoor Life, "The Tongass National Forest is a Wilderness on the Chopping Block," 16 Jan. 2020 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, "Like Fiona, he was born prematurely. Their meeting will melt your heart.," 20 Feb. 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.

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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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Time Traveler for porpoise

Time Traveler

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

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Statistics for porpoise

Last Updated

14 Mar 2020

Cite this Entry

“Porpoise.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porpoise. Accessed 30 Mar. 2020.

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More Definitions for porpoise


How to pronounce porpoise (audio)

English Language Learners Definition of porpoise

: a small usually gray and white whale that has a rounded nose


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

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More from Merriam-Webster on porpoise

Rhyming Dictionary: Words that rhyme with porpoise

Spanish Central: Translation of porpoise

Nglish: Translation of porpoise for Spanish Speakers

Britannica.com: Encyclopedia article about porpoise

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