1. door - Noun
2. door - Verb
An opening in the wall of a house or of an apartment, by which to go in and out; an entrance way.
The frame or barrier of boards, or other material, usually turning on hinges, by which an entrance way into a house or apartment is closed and opened.
Passage; means of approach or access.
An entrance way, but taken in the sense of the house or apartment to which it leads.
Source: Webster's dictionaryhe knocked on the door Source: Internet
he slammed the door as he left Source: Internet
his office is the third door down the hall on the left Source: Internet
the office next door Source: Internet
they live two doors up the street from us Source: Internet
he stuck his head in the doorway Source: Internet