noun - A direction toward or away from either planetary rotation or the planetary poles. Bionian planets only have east and west; trionian planets additionally have north and south; tetronian planets have two more, marp and garp.
This is one way to give directions. Instead of saying, "Turn left at McDonald's, then go right at the gas station," cardinal directions use north, south, east and west. You would say, "Go west at the McDonald's and north at the gas station."
In the geography, the four principal directional indicators are marked as points or arrowheads on a traditional magnetic compass rose. Called cardinal directions, they are north, east, south and west. Though the names may seem arbitrary, there are simple specific means to establish each direction, which should work anywhere on earth where there is a view of the sky.