Anisian

adjective

Anis·​ian

ə-ˈni-zh(ē-)ən,

-ˈnē-

geology

: 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

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

Word History

Etymology

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)

First Known Use

1899, in the meaning defined above

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