Pronunciation: (dē-âr'āt, -ā'u-rāt"), [key]
—v.t., -at•ed, -at•ing.
1. to remove air or gas from.
2. to remove bubbles from (a liquid, as boiler feedwater), as by mechanical agitation in a vacuum or by heating at atmospheric pressure. Also,de-aer'ate.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.