Let us examine some of the many terms that are used to refer to water in soils and rocks. I prefer the simple Anglo-Saxon sounding groundwater. It is so similar to surface water that the parallel is to be appreciated. But many disagreed and go for the Romance language based terms. Here are some definitions—the first five are from the InfoMine dictionary which also has 116 other terms including the word water (by the time you have read them all, you will know all there is to know about water in mining.)


Clear, colorless liquid

Surface Water

Water that rests on the surface of the lithosphere.

Ground Water

1. That part of the subsurface water that is in the zone of saturation, including underground streams.

2. Loosely, all subsurface water as distinct from surface water. Also spelled: groundwater; ground-water.; underground water.

Syn: subterranean water


The science that deals with global water (both liquid and solid), its properties, circulation, and distribution, on and under the Earth's surface and in the atmosphere, from the moment of its precipitation until it is returned to the atmosphere through evapotranspiration or is discharged into the ocean. In recent years, the scope of hydrology has been expanded to include environmental and economic aspects.


A term, often used interchangeably with hydrogeology, referring to the hydrologic or flow characteristics of subsurface waters


Presumably a term used interchangeably with geohydrology.


An instrument for measuring pressure head; usually consisting of a small pipe tapped into the side of a closed or open conduit and flush with the inside; connected with a pressure gage, mercury, water column, or other device for indicating head.

As always, Wikipedia has the most pointed set of definitions:

Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of geologic formations.

A formation of rock or soil is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces become fully saturated with water is called the water table. Groundwater is recharged from, and eventually flows to, the surface naturally; natural discharge often occurs at springs and seeps and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal and industrial use by constructing and operating extraction wells.

The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology. Typically groundwater is thought of as liquid water flowing through shallow aquifers, but technically it can also include soil moisture, permafrost (frozen soil), immobile water in very low permeability bedrock, and deep geothermal or oil formation water.

Then there is Wikipedia on the Vadose Zone:

The vadose zone, also termed the unsaturated zone, is the portion of Earth between the land surface and the phreatic zone or zone of saturation ("vadose" is Latin for "shallow"). Water in the vadose zone has a pressure head less than atmospheric pressure, and is retained by a combination of adhesion (funiculary groundwater), and capillary action (capillary groundwater). If the vadose zone envelops soil, the water contained therein is termed soil moisture.

As always, the Canadian taxpayer supports a site that gives some information of the type generally compiled by summer students. See the Environment Canada site for more on the terminology of groundwater. Or this site from the Alberta Government.

With all due respect to the Canadian taxpayer and Wikipedia, my favorite set of definitions and explanations are at the Groundwater Foundation Kids’ Corner. If you think that is too simplistic, go to the adults’ section.

Finally American taxpayer via the U.S. EPA provides a full set of definitions of terms commonly used in surface and groundwater studies. Invaluable.