Noun. A car crash, particularly multivehicle pileups. Originally from the French game carambole, an older version of billiards played with three balls and no pockets.
The goal is t score points by making shots that have your cue ball carom (collide) with the other two balls.
Like the Viennese terms Kanalforelle (rat,lit. sewer trout), Holzpyjama (coffin, lit. wooden pajamas) or Engerlmocher (archaic. backstreet abortionist,lit. angel maker) a very charming way to describe something rather unpleasant.