stop imagining
A room that has no doors or windows is often referred to as a "mushroom." This is a riddle, playing on the word "room" within "mushroom." In a literal sense, a room without doors or windows would be an enclosed space with no access points.
a mushroom
I mushroom.
A mushroom...
The answer is a mushroom. It has the word room in it. But no walls.
Would that be a mushroom?
no
a mushroom
Fumes from the chemicals can not escape the room if the windows and doors are shut, and are at times toxic.
Question: What kind of room has no doors or windows? Answer: A Mushroom!
A mushroom.