wag one’s chin
wag (one's) chin
To talk or chat, especially idly or at length. A less-common variant of "wag one's tongue." My dad is usually a pretty quiet guy, but get him talking about electrical engineering and he can wag his chin for hours at a time. My wife and her sister haven't seen each other in a while, so they've been wagging their chins all afternoon.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
wag one’s chin
tv. to talk or jabber; to chatter aimlessly. The two old buzzards sat on the park bench wagging their chins all afternoon.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.