Parameter Tree:
EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > GROUND WATER

 Definition:
Ground water in its broadest sense includes all subsurface water whether in its
liquid, solid or gaseous state, provided it is not chemically combined with the
minerals present. In practice, it is all subsurface water that participates in
the hydrological cycle.

Reference:
The Encyclopedic Dictionary of Physical Geography,1997