Someone who is especially lazy, indolent, or given to procrastination. I don't know how a slack master like him manages to get straight A's. That slack master Janet has been pulling our whole project down. I think she's done about 10 minutes of genuine work!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
n. someone who slacks off a lot; someone who doesn’t work hard enough or at all. He never does his share. Nothing but a slackmaster!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.