/ Dictionary / Index C clean room: Meaning and Definition of Find definitions for: clean' room" Pronunciation: [key] a room in which contaminants such as dust are reduced to a very low level by special procedures so that operations such as the manufacture and assembly of delicate equipment or the manipulation of biological materials can be performed effectively. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cleanout cleanse Related Content Daily Word Quiz: digression Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language