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Of, relating to, or being the period of geologic time from about 416 to 359 million years ago, the fourth period of the Paleozoic Era. The Devonian Period is characterized by the development of lobe-finned fishes, the appearance of amphibians and insects, and the first forests. See Table at geologic time.
The Devonian Period.
[After Devon, a county of southwest England.]
1. (Geological Science) 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. (Placename) of or relating to Devon
(Geological Science) the Devonian the Devonian period or rock system
De•vo•ni•an(dəˈvoʊ ni ən)
1. noting or pertaining to a period of the Paleozoic Era, 405 million to 345 million years ago, characterized by the dominance of fishes and the advent of amphibians and ammonites.
2. of or pertaining to Devonshire, England.n.
3. the Devonian Period or System.
[1605–15; < Medieval Latin Devoni(a) Devon + -an1]
The fourth period of the Paleozoic Era, from about 408 to 360 million years ago, characterized by the appearance of forests, amphibians, and insects. See Chart at geologic time.