Cetacean

Part of speech: noun

Pronunciation: /sɪˈteɪʃən/

Definitions

1. A marine mammal with a streamlined body, flippers, and a blowhole for breathing, including whales, dolphins, and porpoises
2. A group of aquatic mammals characterized by their elongated bodies, flippers, and prominent blowholes, encompassing species like dolphins, whales, and porpoises
3. These marine mammals are known for their streamlined forms, including whales and dolphins, and possess blowholes for surface respiration

Etymology: "Cetacean" is a scientific-style coinage built on a Latin word for a sea monster or huge fish. The Latin "cētus" meant "whale," and it came from Greek "kētos," which could denote any large sea creature, including monsters of myth. Modern biologists gathered the group into a formal order called Cetacea, and the adjective-noun "cetacean" was formed by adding the English suffix "-an," which marks membership in or relation to a group. The name thus describes the group by its Latin label rather than by any English folk term. Ordinary speakers had long used "whale" for the largest members and "dolphin" or "porpoise" for smaller ones, and the single word was added to cover all of them under one heading. Its use is a product of formal classification, not of everyday speech.

Synonyms: whale, dolphin, porpoise