One who snaps another's neck with one swift strike of his (or her?) mighty shlong. One who frequents the use of whippersnapping, is referred to as a whippersnappper (commonly by the elderly).
"Jimmy, I don't care how old you are, I swear to the Almighty, if you don't stop calling me a whippersnapper, I'm going to whippersnap your mom's neck off!"
by Pope Zhou III December 7, 2014