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'"
(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