1. A unit of electric current in the meter-kilogram-second system. It is the steady current that, when flowing in straight parallel wires of infinite length and negligible cross section, separated by a distance of one meter in free space, produces a force between the wires of 2 × 10-7 newtons per meter of length.
2. A unit in the International System specified as one International coulomb per second and equal to 0.999835 ampere.