CLOSEST TO THE PIN
Closest to the pin is a contest that is a staple of charity tournaments, corporate outings and similar amateur golf tourneys. On a designated par-3 hole, tee shots that find the green will be measured throughout the day for distance from the flagstick. At the end of the day, the golfer with the best tee shot - the one who was closest to the pin - wins a prize.
The confusion with this term is in its abbreviation: KP. There is no reasoning behind using a K to abbreviate closest; this is simply the way it is.