Erosion

Erosion: Loss of land through water and wind damage.
Etiquette: Code of conduct.
Explode: To play a ball from a bunker moving a large amount of sand. Or what you do if the ball doesn't get out of the bunker.

Third, the teeing ground can be uneven due to erosion or to facilitate drainage. Locate a level spot as you approach the tee; it's tough to tell once you're standing over the ball. If you're still unsure at address, stop and re-tee.

The terrain's drainage pattern has been set by eons of erosion, mostly from water. So the terrain almost always drains towards the nearest pond, creek, river, or the sea.

See also: Press, Woods, Block, Golf, Deep