Paleozoic
Americanadjective
noun
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The era of geologic time from about 540 to 245 million years ago. The beginning of the Paleozoic Era is characterized by a great diversity of marine invertebrate animals. Primitive fish and reptiles, land plants, and insects also first appeared during this time. The end of the Paleozoic is marked by the largest recorded mass extinction in the Earth's history, which wiped out nearly 90% of known marine life forms.
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See Chart at geologic time
Other Word Forms
- post-Paleozoic adjective
- pre-Paleozoic adjective
Etymology
Origin of Paleozoic
1830–40; paleo- + -zoic < Greek zōïkós pertaining to animals; see zo-, -ic
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The skin, which belonged to an early species of Paleozoic reptile, has a pebbled surface and most closely resembles crocodile skin.
From Science Daily • Jan. 11, 2024
Trilobites are early arthropods from the Paleozoic Era.
From Science Daily • Dec. 21, 2023
When the going got tough in the Paleozoic Era, trilobites rolled up.
From New York Times • Dec. 19, 2023
The final meal of this animal—a trilobite—still sat in its guts as sediment buried its body in the sea floor of an ancient Paleozoic sea.
From Science Magazine • Sep. 27, 2023
This happened around 600 million years ago, at the beginning of the Paleozoic era, and accounts for the sudden abundance of marine fossils of all kinds in the record of this period.
From "The Lives of a Cell" by Lewis Thomas
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.