What would you call this room?

It's a small square room where every room in my nieces apartment connects to.

Horrible drawing I know so I want to know what that room would be that has the question mark in it.

It's not a hallway so I don't know the technical definition.

It's a small square room where every room in my nieces apartment connects to.

Horrible drawing I know so I want to know what that room would be that has the question mark in it.

It's not a hallway so I don't know the technical definition.