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

But there are some animals, such as apes, elephants, cetaceans, and others, who are so cognitively complex and autonomous, and whose exploitation is so undeniably frivolous, that leaving their fundamental interests to the vagaries of the humane economy for one day longer is grotesque. —Steven M. Wise, Foreign Affairs, 11 July 2016

The team of expedition guides on my cruise included an ornithologist, cetacean specialist, naturalist, and an ecotoxicologist. —Sarah Greaves-Gabbadon, Travel + Leisure, 15 July 2024

The porpoises, which only live in the northern section of the gulf, have the narrowest range of any cetacean (a classification that includes whales, dolphins and porpoises), according to the National Oceanic and Atmospheric Administration (NOAA). —Brendan Rascius, Miami Herald, 25 July 2024

Explore our new section There are now four cetacean species living in or regularly visiting the busy waters east of the Golden Gate — harbor porpoises, gray whales, humpback whales and bottle-nosed dolphins. —Susanne Rust, Los Angeles Times, 14 July 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