ce·​ta·​cean | \ si-ˈtā-shən How to pronounce cetacean (audio) \

Definition of cetacean

: any of an order (Cetacea) of aquatic mostly marine mammals that includes the whales, dolphins, porpoises, and related forms and that have a torpedo-shaped nearly hairless body, paddle-shaped forelimbs but no hind limbs, one or two nares opening externally at the top of the head, and a horizontally flattened tail used for locomotion

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Other Words from cetacean

cetacean adjective
cetaceous \ si-​ˈtā-​shəs How to pronounce cetaceous (audio) \ adjective

Examples of cetacean in a Sentence

Recent Examples on the Web

The all white belugas are a cold-water species native to the arctic and sub-arctic north whose closest relative among cetaceans is the narwhal. Steve Johnson, chicagotribune.com, "Shedd Aquarium beluga gives birth to healthy calf," 4 July 2019 Although 20 orcas and many other cetaceans continue to live and perform at its facilities, the company increasingly focuses its marketing on its amusement park rides. Natasha Daly, National Geographic, "Orcas don’t do well in captivity. Here’s why.," 25 Mar. 2019 Experts believe the ailing cetacean came into the Bay in late May searching for food and respite from the harsher conditions of the Pacific Ocean. Ashley Mcbride, SFChronicle.com, "Humpback whale takes flight in front of SF skyline in amazing photo," 17 June 2019 Bobbing atop the vast, unforgiving Atlantic in rowboats, whalers face a ghostly white cetacean that has prevailed in all of its previous encounters with puny humankind. Daryl H. Miller, latimes.com, "Review: ‘Moby Dick — Rehearsed’ swims in an ocean of imagination at Theatricum," 14 June 2019 Orcas, dolphins and other cetaceans have made for popular attractions at some aquatic theme parks for decades, but their presence has raised concerns about the ethics of confining whales for the purposes of human entertainment. Anchorage Daily News, "With ‘Free Willy’ bill, Canada bans captivity and breeding of whales and dolphins," 11 June 2019 But researchers recently started referring to an entire class of non-fish seafood that includes cetaceans, other marine mammals and marine reptiles, as aquatic bushmeat. Craig Welch, National Geographic, "More people are eating marine animals—with deadly results," 22 May 2019 Such assessments are of interest to us, and researchers around the globe, with current investigations focused on wildlife such as arboreal mammals and cetaceans. Smithsonian, "When It Comes to Counting Wildlife, Drones Are More Accurate Than People," 27 Feb. 2018 These recent, extreme adaptations raise a question of how cetaceans may continue to change. Brian Switek, Smithsonian, "Today’s Whales Are Huge, But Why Aren’t They Huger?," 27 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cetacean.' 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 cetacean

1835, in the meaning defined above

History and Etymology for cetacean

ultimately from Latin cetus whale, from Greek kētos

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cetane number


Statistics for cetacean

Last Updated

15 Jul 2019

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Time Traveler for cetacean

The first known use of cetacean was in 1835

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English Language Learners Definition of cetacean

technical : a mammal (such as a whale, dolphin, or porpoise) that lives in the ocean

More from Merriam-Webster on cetacean

Britannica.com: Encyclopedia article about cetacean

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