Devonian

American  

[duh-voh-nee-uhn] / dəˈvoʊ ni ən /

adjective

1. Geology. noting or pertaining to a period of the Paleozoic Era, 405 to 345 million years ago, characterized by the dominance of fishes and the advent of amphibians and ammonites.

2. of or relating to Devonshire, England.

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noun

1. Geology. the Devonian Period or System.

Devonian British  

/ dəˈvəʊnɪən /

adjective

1. of, denoting, or formed in the fourth period of the Palaeozoic era, between the Silurian and Carboniferous periods, lasting 60-70 million years during which amphibians first appeared

2. of or relating to Devon

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noun

1. the Devonian period or rock system

Devonian Scientific  

/ dĭ-vō′nē-ən /

1. The fourth period of the Paleozoic Era, from about 408 to 360 million years ago. During this time there were three major landmasses: most of modern day North America and Europe were located along the equator; a portion of Siberia was located to the north; and a continent consisting of South America, Australia, Africa, India, and Antarctica was located in the Southern Hemisphere. In the early Devonian small plants dominated the landscape, but by the end of the Devonian ferns and seed plants had appeared, as had the first forests. The first tetrapods (terrestrial vertebrates) and terrestrial arthropods appeared, as did many new types of fish.

2. See Chart at geologic time

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Other Word Forms

• post-Devonian adjective

Etymology

Origin of Devonian

1605–15; < Medieval Latin Devoni ( a ) Devon + -an

Example Sentences

"The exceptional lungfish skull unearthed in 410 million-year-old rocks in Yunnan gives us major insights into the rapid evolutionary diversification between the early-, mid- and late Devonian."

From Science Daily • Mar. 12, 2026

The tea plants in lunar soil flourished, performing on par with those in Devonian soil, while the Mars saplings failed to grow.

From Salon • Sep. 29, 2025

The lunar and Martian samples were compared against a control group grown in Devonian soil, an ancient, clay-rich type from Devon, England.

From Salon • Sep. 29, 2025

"The Devonian period fundamentally changed life on Earth," said Professor Neil Davies from Cambridge's Department of Earth Sciences, the study's first author.

From Science Daily • Mar. 7, 2024

Some sense of the strength of feeling can be gained by glancing through the chapter titles of Martin J. S. Rudwick’s excellent and somber account of the issue, The Great Devonian Controversy.

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