Anis·​ian | \ ə-ˈni-zh(ē-)ən, -ˈnē- \

Definition of Anisian

: of, relating to, or being the earliest division of the Middle Triassic lasting from approximately 245 million years ago until 237 million years ago However, vertebrate paleontological evidence, as yet unsupported by palynology, seems to show that some associated sediment of the Fundy Basin probably is even older than Ladinian, referable to the preceding Anisian Stage.— Alfred Traverse, Science, 12 June 1987 — see Geologic Time Table

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Other Words from Anisian

Anisian noun
The first normal marine gastropod assemblages appeared during the Anisian, at the time of the general reappearance of marine communities. Evolutionary Paleobiology, 1996

First Known Use of Anisian

1899, in the meaning defined above

History and Etymology for Anisian

borrowed from German Anisisch (with -ian replacing German -isch), derivative of Late Latin Anisus, ancient name of the river Enns (alluding to the type locality at Gross-Reifling, in the Enns Valley in Styria, Austria)

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The first known use of Anisian was in 1899

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anisic acid

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Cite this Entry

“Anisian.” Dictionary, Merriam-Webster, Accessed 24 Oct. 2021.

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