aquitard

noun
aqui·​tard | \ˈa-kwə-ˌtärd \
plural aquitards

Definition of aquitard 

geology

: a geologic formation or stratum that lies adjacent to an aquifer and that allows only a small amount of liquid to pass If the water level—and thus the pressure—drops enough, water is slowly squeezed out of the large clayey layers—called aquitards—that more or less seal the aquifer, and an aquifer's compression becomes irreversible.— Peter Bacque, Richmond (Virginia) Times Dispatch, 14 Nov. 2002

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First Known Use of aquitard

1965, in the meaning defined above

History and Etymology for aquitard

probably from aqui- (in aquifer) + (re)tard

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Dictionary Entries near aquitard

Aquino

Aquitaine

Aquitania

aquitard

aquiver

aquo-

aquo

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The first known use of aquitard was in 1965

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