1. To sink, settle, or droop away (from something). I hate the way my skin sags away in certain places. Just another wonderful perk of getting old, I suppose. Over the years, the dilapidated porch began sagging away from the rest of the house, until, one morning, it finally collapsed entirely.
2. In a boat, to drift continuously to leeward. With the rudder broken, we sagged away to leeward, completely at the mercy of the winds and the tides. I let the boat sag away south by southwest, intending to swing the sails around and take advantage of a clean line of wind to push us across the finish line.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
sag away (from something)
to settle or droop down or away. The cloth sagged away from the edge of the table.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.