I’m trying to think of another term for a room, such as a waiting room. I think, it may (also) be used to describe a room within a larger room, such as found in some older style offices where the secretary would sit near the boss.
I want to say it might begin with a prefix, such as the "pre-"something room?
As I say, it may be an old-fashioned word nowadays. Any takers? WAGs?