Noun
aquitard (plural aquitards)
(geology) A semipermeable layer along an aquifer.
An aquitard can sometimes, if completely impermeable, be called an aquiclude or aquifuge. Source: Internet
Related terms include aquitard, which is a bed of low permeability along an aquifer, citation and aquiclude (or aquifuge), which is a solid, impermeable area underlying or overlying an aquifer. Source: Internet
The system shows two aquifers with one aquitard (a confining or impermeable layer) between them, surrounded by the bedrock aquiclude, which is in contact with a gaining stream (typical in humid regions). Source: Internet