ESTA Electrical Standards definition:
An electrical issue that occurs when the load on a circuit of some sort is circumnavigated by a lower-resistance means, such as a wire. For example, if one mistakenly soldered all of the pins in an XLR connector together, a short would be the result. A short circuit, or "short", will usually cause some form of problem, ranging from a blown fuse or tripped breaker to total destruction of whatever is connected (a cable, for instance, might be burned up by the increased current in the conductor if a fuse is shorted out)