slang To sleep. In illustrations such as comics, three (or more) Z's are often used to represent sleep or snoring. I'm hoping to blow some Z's during the long layover before our next flight. It's been a hard week for Jeff—he needs to blow some Z's.
See also: blow
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
tv. to sleep. I got to blow Zs for a while; then we’ll talk.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.