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

The bill bans importing, exporting, keeping and breeding whales, dolphins and porpoises, as well as making the animals perform for entertainment. Helen Murphy, PEOPLE.com, "Canada Passes Ban Making It Illegal to Keep Dolphins and Whales in Captivity," 11 June 2019 Several studies show the gray seals can sometimes attack and eat harbor porpoises and harbor seals. Bethany Augliere, National Geographic, "Cannibalism is more common than thought in gray seals," 24 Apr. 2019 The nets also drown vaquitas, a small porpoise that lives only in the Gulf — also known as the Sea of Cortes — of which perhaps as few as 10 remain. Mark Stevenson, The Seattle Times, "Mexican Navy: 1 injured in clash near vaquita reserve," 29 Mar. 2019 Orcas have the most varied diet of any whale, dolphin or porpoise, and can take on prey of all types, from stingrays to salmon, depending on the type of orca. Lynda V. Mapes, The Seattle Times, "What you need to know about the critically endangered southern resident killer whales," 25 Sep. 2018 Indeed, there is evidence that many cetaceans—that is, whales, dolphins and porpoises—have strong and complicated family and social ties. Alison Gopnik, WSJ, "Like Us, Whales May Be Smart Because They’re Social," 16 Aug. 2018 The red tide has made breathing difficult for locals, scared away tourists, and strewn popular beaches with the stinking carcasses of fish, eels, porpoises, turtles, manatees and one 26-foot whale shark. Kate Furby, The Seattle Times, "Red tide algae’s deadly toll on sea life has triggered a state of emergency in Florida," 14 Aug. 2018 Harbor porpoises, the smallest dolphin species found in New England, usually measure 4.5 feet to 6 feet and weigh less than 200 pounds. Laney Ruckstuhl, BostonGlobe.com, "Pregnant porpoise dies on Dorchester Bay shore during the last nor’easter," 10 Mar. 2018 A decade of rescue crusades by conservation groups, hard-core eco-activists and the U.S. Navy have failed to prevent the world’s rarest porpoise from becoming fatally entangled in gill nets set for seafood in Mexico’s northern Gulf of California. Louis Sahagun, latimes.com, "To save the world's rarest marine mammal, conservationists seek ban on Mexican seafood imports," 11 July 2018

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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Statistics for porpoise

Last Updated

21 Jun 2019

Look-up Popularity

Time Traveler for porpoise

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

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More Definitions for porpoise



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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