While the source of the word kvort is debatable (and I am not convinced that it's not a Yiddishification of quart), I can't forget how I was once sitting with some young business associates in Williamsburg and was telling a certain story. In one of the sentences I was saying something about א פאר פאלק and was greeted with dumb stares, until one guy finally exclaims: אהה, דו מיינסט א קאפל!