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

Students and volunteers join habitat restorations, sea‑turtle monitoring, research into dolphins and other cetaceans, and beach cleanups — work that both builds resumes and roots students in place. —Emily Bramhall, Miami Herald, 20 Nov. 2025

That's where the marine animals push smaller cetaceans with their snouts or hold and carry them in their mouths, occasionally tossing them into the air, according to the Encyclopedia of Puget Sound. —Saman Shafiq, USA Today, 18 Nov. 2025

In addition to its pod, the sizable cetacean generally hosts dozens of remoras. —Andrew Paul, Popular Science, 5 Nov. 2025

But to do so would be like analyzing Moby-Dick as a field guide to cetaceans—instructive in its way but kind of missing the point. —Scott Stossel, The Atlantic, 9 Sep. 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