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

Their initial study was published this week in the journal Science, reconstructing CO2 concentrations going back through the Cenozoic, the era that began with the demise dinosaurs and rise of mammals 66 million years ago.

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

Texas’ ancient outcrops record broad swaths of the last 300 million years, including Carboniferous coal swamps, dinosaur-filled floodplains and Cenozoic savannas.

From New York Times • Jul. 17, 2023

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