1. The face of a die that bears two spots
2. A playing card bearing an index number two
3. A throw of the dice yielding two points
4. [obsolete English deuce bad luck] Devil, dickens — used chiefly as a mild oath; something notable of its kind
5. One of four cards in a deck having two spots.

The cardinal number that is the sum of one and one or a numeral representing this number; SYN. 2, II, deuce.