(idiom) To close down a business permanently; often used jokingly or sarcastically to describe a shop or factory going out of business.

The last disciple accepted by a master, after whom the master stops taking students.

to close the doors and windows to ensure security or privacy

lit. shut the door and beat the dog; to seal off the enemy's escape route before launching an attack to wipe them out

to take precautions after the event; to be too late; to shut the gate after the thief has already gone

To take precautions only after a disaster or loss has already occurred; similar to the English idiom "to lock the stable door after the horse has bolted".

(variant form) to lock the door after the thief has already gone; to take precautions only after the damage is done

Closed-doorism or exclusivism; refers to a narrow political tendency to reject alliances with others or refuse to recruit qualified members, especially within a revolutionary party.

(idiom) To catch a thief by closing his escape route; specifically, to surround a small enemy force to prevent their escape and avoid a desperate counter-attack.

to close the door and lock it

To close the door and slide the bolt; metaphorically refers to a matter that is settled and cannot be changed