Aalenian

adjective

Aa·​le·​ni·​an ä-ˈlē-nē-ən 

: of, relating to, or being a period of the Middle Jurassic lasting from approximately 176 million years ago until 172 million years ago

This applies particularly to the thickest of the sandstones, the Bearreraig Sandstone of Aalenian to Bajocian age.

—J. D. Hudson et al., Journal of the Geological Society, September 2011

see Geologic Time Table

Aalenian noun

Subsequently, during the Aalenian, the motile forms (still present in the water column) had become adapted to life in stressed salinities …

—Alister James Powell and J. B. Riding, Recent Developments in Applied Biostratigraphy, 2005

Word History

Etymology

borrowed from French aalénien, from Aalen, town in Württemberg, Germany, the location of strata defining the period + -ien -ian

First Known Use

1882, in the meaning defined above

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