The following glossary of medical terms was assembled as part of a project on medicine from 1760-1830 but it includes some terms from a wider period. I have drawn on several sources, including, with the permission of the author, Medical Terms used in the late 18th Century which appeared on a now obsolete web site written my Melanie McClusky. Information from Dr Johnson's Dictionary, first published in 1755, is shown in red.
Figure 2 is a simple cartoon showing three different types of aquifers: confined, unconfined, and perched. Recharge zones are typically at higher altitudes but can occur wherever water enters an aquifer, such as from rain, snowmelt, river and reservoir leakage, or from irrigation.
An aquifer is a layer or zone below the surface of the earth which is capable of yielding a significant volume of water. Aquifers may occur at various depths. Those closer to the surface are more likely to be used for water supply and irrigation, as well as more likely to be topped off by local rainfall.