a swinging or sliding barrier that will close the entrance to a room or building or vehicle; "he knocked on the door"; "he slammed the door as he left"
a room that is entered via a door; "his office is the third door down the hall on the left"
a structure where people live or work (usually ordered along a street or road); "the office next door"; "they live two doors up the street from us"
anything providing a means of access (or escape); "we closed the door to Haitian immigrants"; "education is the door to success"
consisting of or containing or of the nature of crystals; "granite is crystalline"
transmitting light; able to be seen through with clarity; "the cold crystalline water of melted snow"; "crystal clear skies"; "could see the sand on the bottom of the limpid pool"; "lucid air"; "a pellucid brook"; "transparent crystal"
distinctly or sharply outlined; "crystalline sharpness of outline"- John Buchan