Fatigues, referring to the clothing worn by members of the military. Based on an intentional mispronunciation of "fatigues." Does everyone on the base have to wear fattygews?
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
n. fatigues. (Originally military.) I’ll slip into some fattygews and be right with you.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.