loose-butt hinge

loose-joint hinge, heave-off hinge, lift-off hinge, loose-joint butt

loose-joint hinge
A door hinge having two knuckles, one of which has a vertical pin (at its center) that fits in a corresponding hole in the other; by lifting the door up, off the vertical pin, the door may be removed without unscrewing the hinges.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.