fog over(redirected from fogs over)
To become obscured by fog. My glasses fogged over while I was in the shower—I can't see a thing!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
[for something made of glass] to become covered over with water vapor. The windshield fogged over because I forgot to turn on the defroster. The mirror fogged over, and I couldn't see to shave.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.