If you are outside a room, you are not in it but are in the passage or area next to it. She'd sent him outside the classroom He stood in the narrow hallway just outside the door. inside Outside is also an adverb. They heard voices coming from outside in the corridor inside
The part or space which lies without an inclosure; the outer side, as of a door, walk, or boundary
located, suited for, or taking place in the open air; "outdoor clothes"; "badminton and other outdoor games"; "a beautiful outdoor setting for the wedding"
On or to the outside (of); without; on the exterior; as, to ride outside the coach; he stayed outside
Outside people or organizations are not part of a particular organization or group. The company now makes much greater use of outside consultants. Outside is also a preposition. He is hoping to recruit a chairman from outside the company
coming from the outside; "extraneous light in the camera spoiled the photograph"; "relying upon an extraneous income"; "disdaining outside pressure groups"