look up any word, like darude - sandstorm:
 
2.
Noun. In bike racing, the sag wagon is a support vehicle that picks up riders unable to complete a road race because of injury, mechanical problem or other mishap.
__Oww, man, Lookit my bike! I'm not gonna be able to finish the race on this potato-chipped front wheel.
__Too bad man, but don't worry. The sag wagon will pick you up in a few minutes and give you a lift to the mechanic.
by Brian the bike commuter June 12, 2008
 
1.
Large breasts that hang like a wang.
Lisa O has huge sag wagons!
by JayChap January 30, 2008