backroom

noun

1. (attributive, figuratively, often)A room near the rear of a premises.

   “Near-synonym: smoke-filled room (meeting place of crooked insiders)”

   “backroom deals”

   “backroom bargaining”

   “It is known that means of using this end of the former NLR and Broad Street station to take an overspill of traffic from Liverpool Street have been under backroom study for some time.”

   “The vote for a new prime minister will involve plenty of backroom bargaining, while Thailand struggles to revive its faltering economy.”

2. A room near the rear of a premises.

   “We had thought that they were out of the old model, but somebody checked in the backroom and found a case of them.”