This term is used in pool and billiards as an alternative to the word break. It is most often heard as part of the expression "on the snap".
During a recent pool tournament, The Midwest Nine Ball Tour, held at Shooter's in Olathe, KS many of the participants made the "nine on the snap". Unfortunately for them a few players scratched at the same time.
Onomatopoeia is the source for this word.