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

According to a May publication in the Journal of Wildlife Diseases, researchers at UH Mānoa and the College of Tropical Agriculture and Human Resilience found Brucella infections in seven species of cetaceans from 2000 to 2024, with striped dolphins showing the highest prevalence. —Thomas Westerholm, MSNBC Newsweek, 25 June 2025

Their analysis revealed that 71 of the tools were made from the bones of cetaceans, the group of marine mammals that includes whales, dolphins and porpoises. —Sarah Kuta, Smithsonian Magazine, 28 May 2025

Smaller shark species such as requiem sharks and ancestors of today’s cetaceans, dolphins and whales, were next. —David Bressan, Forbes.com, 26 May 2025

Such evidence could support the view that incessant loud noise amounts to torture or cruel treatment towards cetaceans, in turn galvanizing support for a new right to be free from such harm. —David Gruber, Time, 24 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