green room noun2 •In a television studio, theatre or concert hall, the room where performers await their entrance.There are three smaller rooms he can use as rehearsal space or dressing rooms or green rooms, according to need. — 2016 •The inside of a tube (a cylindrical wave).Never quite got covered up, but stood in the doorway to the green room with the lip feathering over my shoulders several times — 1996 formsgreen rooms · green-rooms
