A parp which is so epic, so explosive, so traumatic and so voluminously productive that:
1) The person who produced it may suffer from loss of consciousness, rectal prolapse, bleeding hemorrhoids and ruined underwear.
2) Those in the immediate vicinity may suffer from nausea, vomiting, and light headedness.
3) There is typically a very large, brown mess left behind due to the volume of intestinal gas released and the violence with which it was ejected.
"Dude I was chillin over at Steves house man, and this other dude walked by, and he straight busted out a giga-parp right by my face. Man that shit was nasty, I felt the wind hit my face and blew chunks right off, but that dude passed out yo and he had shit running out his pants. Everyone in the room was gagging man, we all bailed."