an electric railway operating below the surface of the ground (usually in a city); "in Paris the subway system is called the `metro' and in London it is called the `tube' or the `underground'"
a line spoken by an actor to the audience but not intended for others on the stage
in reserve; not for immediate use; "started setting aside money to buy a car"; "put something by for her old age"; "has a nest egg tucked away for a rainy day"
on or to one side; "step aside"; "stood aside to let him pass"; "threw the book aside"; "put her sewing aside when he entered"
out of the way (especially away from one's thoughts); "brush the objections aside"; "pushed all doubts away"
placed or kept separate and distinct as for a purpose; "had a feeling of being set apart"; "quality sets it apart"; "a day set aside for relaxing"
the level of official classification for documents next above restricted and below secret; available only to persons authorized to see documents so classified
denoting confidence or intimacy; "a confidential approach"; "in confidential tone of voice"
(of information) given in confidence or in secret; "this arrangement must be kept confidential"; "their secret communications"
entrusted with private information and the confidence of another; "a confidential secretary"
(chemistry) a surface forming a common boundary between two things (two objects or liquids or chemical phases)
(computer science) computer circuit consisting of the hardware and associated circuitry that links one device with another (especially a computer and a hard disk drive or other peripherals)
the overlap where two theories or phenomena affect each other or have links with each other; "the interface between chemistry and biology"
(computer science) a program that controls a display for the user (usually on a computer monitor) and that allows the user to interact with the system
(medicine) the act of caring for someone (as by medication or remedial training etc.); "the quarterback is undergoing treatment for a knee injury"; "he tried every treatment the doctors suggested"; "heat therapy gave the best relief"