Cretaceous

adjective

Cre·​ta·​ceous kri-ˈtā-shəs How to pronounce Cretaceous (audio)
: of, relating to, or being the last period of the Mesozoic era characterized by continued dominance of reptiles, emergent dominance of angiosperms, diversification of mammals, and the extinction of many types of organisms at the close of the period
also : of, relating to, or being the corresponding system of rocks see Geologic Time Table
Cretaceous noun

Examples of Cretaceous in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The water hole was surrounded by palm trees and sand dunes during the late Cretaceous period, but since then, the environment has changed drastically. — Irene Wright, Miami Herald, 5 Mar. 2025 There's a model of Hadrosaurus in the museum's Cretaceous galleries, but this is not an ordinary dinosaur museum. — Phaedra Trethan, USA TODAY, 1 Mar. 2025 In woodlands much like this one in prehistoric Myanmar, from equatorial forests to those that survive through the long dormancy of polar nights, pieces of Cretaceous life are becoming encased in resin. — Riley Black, Smithsonian Magazine, 27 Feb. 2025 These teeth spanned a wide age range, from the modern era back to the Cretaceous period. — Melissa Cristina Márquez, Forbes, 1 Mar. 2025 See All Example Sentences for Cretaceous

Word History

Etymology

Latin cretaceus resembling chalk, from creta chalk

First Known Use

1832, in the meaning defined above

Time Traveler
The first known use of Cretaceous was in 1832

Rhymes for Cretaceous

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Cretaceous
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“Cretaceous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Cretaceous. Accessed 25 Mar. 2025.

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Kids Definition

Cretaceous

adjective
Cre·​ta·​ceous kri-ˈtā-shəs How to pronounce Cretaceous (audio)
: of, relating to, or being the last period of the Mesozoic era of geological history marked by the extinction of the dinosaurs at the close of the period
also : relating to the corresponding system of rocks see geologic time
Cretaceous noun
Last Updated: - Updated example sentences
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