aquitard

noun aqui·tard \ ˈa-kwə-ˌtärd \

Definition of aquitard

plural aquitards
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 BacqueRichmond (Virginia) Times Dispatch14 Nov. 2002

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Origin and Etymology of aquitard

probably from aqui- (inaquifer) +1(re)tard


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