Also called nose bag. a bag for feeding horses, placed before the mouth and fastened around the head with straps.
put on the feed bag, Slang. to have a meal; eat: When his friends put on the feed bag, they finish everything in sight.
Origin of feed bag
An Americanism dating back to 1830–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
put on the feed bag
Also, tie on the feed bag. Eat a meal, as in Come on, it's time to put on the feed bag. This slangy term, alluding to a horse's feed bag that is literally tied on, dates from the early 1900s.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.