cetacean

noun

ce·​ta·​cean si-ˈtā-shən 

: 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

cetacean adjective

cetaceous

si-ˈtā-shəs 

adjective

Examples of cetacean in a Sentence

Recent Examples on the Web

Other cetaceans in the region, especially the migratory species, will not seek any encounters. —Emese MacZko, Forbes.com, 31 Mar. 2025

What originally appeared to be attacks on more than 673 boats since 2020 now seem more likely to be a bunch of bored teenage orcas looking for something to do, said cetacean expert Alexandre Zerbini. —Elizabeth Weise, USA TODAY, 24 May 2024

Importantly, this new science could converge with Indigenous peoples’ ancestral knowledge of and relations with cetaceans, which recently led Indigenous leaders of New Zealand, Tahiti, and the Cook Islands to sign a treaty recognizing the legal personhood of cetaceans. —David Gruber, Time, 24 Apr. 2025

Matthew Wills September 6, 2022 Whale-watching cruises can negatively affect the behavior of cetaceans, depending on species, environment, and population. —The Editors, JSTOR Daily, 22 Apr. 2025

Word History

Etymology

ultimately from Latin cetus whale, from Greek kētos

First Known Use

1840, in the meaning defined above

Rhymes for cetacean

• ablation
• bination
• carnation
• cassation
• castration
• causation
• centration
• cessation
• chelation
• citation
• collation
• conflation

Kids Definition

cetacean

noun

ce·​ta·​cean si-ˈtā-shən 

: any of an order of aquatic mammals (as a whale, dolphin, or porpoise)

cetacean adjective