backroom

noun

1. a room located in the rear, especially one used only by certain people.
2. a place where powerful or influential persons, especially politicians, meet to plan secretly or from which they exercise control in an indirect manner: The candidate for mayor was chosen in the precincts’ back rooms.

noun

1. 1. a place where research or planning is done, esp secret research in wartime
   2. (as modifier)back-room boys