oil well

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A hole drilled or dug in the earth from which petroleum flows or is pumped.

from The Century Dictionary.

• noun An oil-cellar; a dish or receptacle, under a bearing, filled with oil to furnish a supply for the bearing.
• noun A boring made for petroleum.

from the GNU version of the Collaborative International Dictionary of English.

• noun A well{3} from which petroleum is or has been extracted; a well{3} drilled deeply into an oil-bearing geological formation specifically for the purpose of obtaining petroleum.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A hole drilled into the earth from which petroleum is pumped

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a well that yields or has yielded oil