reflux condenser

from The Century Dictionary.

• See condenser.

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

• noun chemistry A water-cooled, double walled piece of laboratory glassware that is fitted on top of a vessel of boiling liquid such that vapour condenses and flows back into the vessel, preventing the contents from boiling dry.

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

• noun condenser such that vapor over a boiling liquid is condensed and flows back into the vessel to prevent its contents from boiling dry