Cenozoic

American  

[see-nuh-zoh-ik, sen-uh-] / ˌsi nəˈzoʊ ɪk, ˌsɛn ə- /

adjective

1. noting or pertaining to the present era, beginning 65 million years ago and characterized by the ascendancy of mammals.

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noun

1. the Cenozoic Era or group of systems.

Cenozoic British  

/ ˌsiːnəʊˈzəʊɪk /

adjective

1. of, denoting, or relating to the most recent geological era, which began 65 000 000 years ago: characterized by the development and increase of the mammals

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noun

1. the Cenozoic era

Cenozoic Scientific  

/ sĕn′ə-zō′ĭk /

1. The most recent era of geologic time, from about 65 million years ago to the present. The Cenozoic Era is characterized by the formation of modern continents and the diversification of mammals and plants. Grasses also evolved during the Cenozoic. The climate was warm and tropical toward the beginning of the era and cooled significantly in the second half, leading to several ice ages. Humans first appeared near the end of this era.

2. See Chart at geologic time

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Etymology

Origin of Cenozoic

First recorded in 1850–55; ceno- ¹ + zo- + -ic

Example Sentences

During the Cenozoic, for example, long-term declines in CO2 and associated climate cooling may have driven changes to plant physiology, species competition and dominance, which in turn impacted mammalian evolution.

From Science Daily • Dec. 7, 2023

The specimen belongs to the species Anachlysictis gracilis, which is part of a group of extinct predatory mammals known as sparassodonts, that lived in South America during the Cenozoic, after the extinction of the dinosaurs.

From Science Daily • Oct. 12, 2023

Already competing to survive, ginkgos began to disappear from North America and Europe during the Cenozoic Era, a time of global cooling that began around 66 million years ago.

From National Geographic • Oct. 4, 2023

Mammal skulls from the Cenozoic era tend to shatter around the opening of the snout, he said, while crocodile skulls often break at a weak spot between the eyes.

From New York Times • Dec. 26, 2022

Sometimes too you will see the term Phanerozoic used to describe the span encompassing the Cenozoic, Mesozoic, and Paleozoic eras.

From "A Short History of Nearly Everything" by Bill Bryson