From WordNet (r) 3.0 (2006) [wn]:
doorway
n 1: the entrance (the space in a wall) through which you enter
or leave a room or building; the space that a door can
close; "he stuck his head in the doorway" [syn: doorway,
door, room access, threshold]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Doorway \Door"way`\, n.
The passage of a door; entrance way into a house or a room.
[1913 Webster]