from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. become flat or flatter
Sorry, no etymologies found.
But things had begun to flatten out a bit, and Highway 50, the winding two-lane highway we’d been on since leaving Yosemite changed to four-lanes, with two going each way.
The Aerospatiale engine overhead shrieked to life, and the Dolphin's sagging thirty-nine-foot rotors began to flatten out into a silver blur.