Definitions of W:

noun: the 23rd letter of the Roman alphabet
noun: a unit of power equal to 1 joule per second; the power dissipated by a current of 1 ampere flowing across a resistance of 1 ohm
noun: the cardinal compass point that is a 270 degrees
noun: a heavy gray-white metallic element; the pure form is used mainly in electrical applications; it is found in several ores including wolframite and scheelite