When you get fucked up

If you are in a red car and you pass another car, you are obligated to flash your headlights and yell "Kachow!" Or when you get into a car accident.

Yes my dude

The term that was banned at my school because my teacher looked on Urban dictionary.

when you're too cool

Also commonly referred to the classic catchphrase of the notorious "Lightning McQueen", kachow is a term that is used as a reference to when a man sneezes while taking a piss resulting in a "KACHOW". A kachow can only be avoided if the victim starts to force his piss stream to a higher PSI, or just holding in the sneeze.