Borehole vs. Corehole

Boreholenoun

A hole bored into the ground to collect samples for analysis or to extract oil or water.

Boreholeverb

(ambitransitive) To bore a hole of this kind (in).

Borehole

A borehole is a narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water, other liquids (such as petroleum) or gases (such as natural gas), as part of a geotechnical investigation, environmental site assessment, mineral exploration, temperature measurement, as a pilot hole for installing piers or underground utilities, for geothermal installations, or for underground storage of unwanted substances, e.g.

Coreholenoun

The hole drilled to retrieve a core sample.