chafing dish

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

• noun A metal dish or pan mounted above a heating device and used to cook food or keep it warm at the table.

from The Century Dictionary.

• noun A dish or vessel to hold coals for heating anything set on it; a portable grate for coals.
• noun A dish fitted with such a vessel for hot coals, or with lamps or the like beneath, and having a cover, used for keeping meat and other food hot.

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

• noun cooking Any of several devices, involving a pan and a heater, used to warm food at the table, or to keep it warm.

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

• noun a metal pan over a heater; used to cook or to keep things warm at the table