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

However, none of this explains exactly how the diminutive creature evolved into massive cetaceans. —Scott Travers, Forbes, 7 Dec. 2024

So bats, the cetaceans — basically those are whales and dolphins, all right? —Janna Levin, Quanta Magazine, 21 Nov. 2024

But unlike cetaceans, there came a point when thallatosuchian snout sinuses (particularly those of metriorhynchids) started to expand instead of shrink. —Andrew Paul, Popular Science, 30 Oct. 2024

So have several cetaceans—most famously, an orca known as Tahlequah, who, without the primate’s advantage of hands, carried her deceased infant on her back continuously for weeks, across more than a thousand miles of the Salish Sea. —Kathryn Schulz, The New Yorker, 28 Oct. 2024

Word History

Etymology

ultimately from Latin cetus whale, from Greek kētos

First Known Use

1840, in the meaning defined above

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