Origin: Old English bereærn, from bere barley + ærn place
1 a large farm building for storing crops, or for keeping animals in2informal a large plain building: a huge barn of a house3close the barn door after the horse has left/escaped/fled etc. to try to prevent something when it is too late and harm has already been done [Origin: Old English bereærn, from bere barley + ærn place]