cretaceous

American  

[kri-tey-shuhs] / krɪˈteɪ ʃəs /

adjective

1. resembling or containing chalk.

2. (initial capital letter)  noting or pertaining to a period of the Mesozoic Era, from 140 million to 65 million years ago, characterized by the greatest development and subsequent extinction of dinosaurs and the advent of flowering plants and modern insects.

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noun

1. (initial capital letter)  the Cretaceous Period or System.

Cretaceous ¹ British  

/ krɪˈteɪʃəs /

adjective

1. of, denoting, or formed in the last period of the Mesozoic era, between the Jurassic and Tertiary periods, lasting 80 million years during which chalk deposits were formed and flowering plants first appeared

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noun

1. the Cretaceous period or rock system

cretaceous ² British  

/ krɪˈteɪʃəs /

adjective

1. consisting of or resembling chalk

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Cretaceous Scientific  

/ krĭ-tā′shəs /

1. The third and last period of the Mesozoic Era, from about 144 to 65 million years ago. During this time the supercontinent Pangaea continued to split up, with modern-day South America and Africa splitting apart, the Atlantic Ocean widening, and India disconnecting itself entirely from the other landmasses to which it was attached. Dinosaurs continued to be the dominant terrestrial animals, but many insect groups, modern mammals and birds, and the angiosperms (flowering plants) also first appeared. The Cretaceous Period ended with a mass extinction event in which about 75 percent of all species, including marine, freshwater, and terrestrial organisms, became extinct.

2. See Chart at geologic time

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Other Word Forms

• cretaceously adverb
• noncretaceous adjective
• postcretaceous adjective
• supercretaceous adjective

Etymology

Origin of cretaceous

1665–70; < Latin crētāceus, equivalent to crēt ( a ) chalk, clay ( crayon ) + -āceus -aceous; the geological period was defined from the chalk beds of SE England and associated formations

Example Sentences

Outside are nature trails, a “cretaceous” garden and a playground with a pterosaur-themed structure and a sandbox concealing replica dinosaur bones.

From The Wall Street Journal

The new pterosaurs – identified from chunks of jaws and teeth found in the middle cretaceous Kem Kem beds of Morocco – had wingspans of three to four metres.

From The Guardian

Earliest known mammalian stapes from an early cretaceous eutriconodontan mammal and implications for evolution of mammalian middle ear.

From Nature

American Ninja Warrior turned into Jurassic Park when a “carnivore from the cretaceous period” invaded the obstacle course—a Tyrannosaurus Rex.

From Time

For the animals of the late cretaceous, S. electri was probably not very good eating.

From BBC