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 That could be because commercial whaling bans have boosted the number of cetaceans in the sea, allowing whales to find mates without having to shout. Emily Anthes, New York Times, "The Sound of One Shrimp Snapping," 21 Apr. 2020 This differs from cetaceans, which miniaturized their bony labyrinths soon after entering the water. Fox News, "Prehistoric crocodiles were more like whales and dolphins, shocking study finds," 21 Apr. 2020 Now, 13 small cetacean species are nearing extinction primarily because of these nets, marine biologists report this month in Endangered Species Research. Virginia Morell, Science | AAAS, "Modern fishing methods are driving small whales and dolphins to extinction," 11 Dec. 2019 While most cetaceans' pectoral fins are only one-seventh of their body length, a humpback's flippers can reach up to one-third of its body length. Brigit Katz, Smithsonian, "Watch Humpback Whales Scoop Fish Into Their Mouths Using Their Fins," 17 Oct. 2019 After the earthquake, the team used directional hydrophones to tune into the cetaceans' sounds, and then traveled to the source in their boat. National Geographic, "Earthquakes can make it harder for whales to find food, first-ever study says," 31 Jan. 2020 Another subset became more and more aquatic, sprouting its own branches that eventually spun off the first cetaceans to live in the seas for their entire lives. Riley Black, Smithsonian, "Ancient Whale Fossil Helps Detail How the Mammals Took From Land to Sea," 11 Dec. 2019 Many of the cetaceans tagged in Mul’s study have visible scars from entanglement with fishing nets, collisions with boat hulls or propellers. Chiara Eisner, Scientific American, "Arctic Exploitation May Harm Animals Large and Small," 5 Mar. 2020 The whales, expected to reach 35 to 50 years of age, will be the first aquatic animals to inhabit the sanctuary for cetaceans off Iceland’s southern coast. Washington Post, "Whales from Chinese aquarium starting retirement in Iceland," 19 June 2019

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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Time Traveler for cetacean

Time Traveler

The first known use of cetacean was in 1835

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Statistics for cetacean

Last Updated

19 May 2020

Cite this Entry

“Cetacean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cetacean. Accessed 4 Jul. 2020.

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How to pronounce cetacean (audio)

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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