A verbalization, or onomatopoeia, of a really gigantic explosion.
Saddam was hanging out in Baghdad one day in March when all of a sudden - fwackoom! - half the city was vaporized by an American airstike.
by bjorn_skurj December 30, 2003
1 more definition
To destroy with a really impressively cool magic attack.
"Look! I'm fwackooming your king!"
by Tom December 28, 2003