A progressive parlay is a joint wager on multiple events, for example team sports or horse races, however, unlike a regular parlay, if some of the individual bets lose, but most win, the bettor still wins, although with a much smaller payout, what is called, an accumulator, or combo bet is a single bet that links together two or more individual wagers and is dependent on all of those wagers winning together?
Progressive parlay:  However, unlike a regular parlay, if some of the individual bets lose, but most win, the bettor still wins, although with a much smaller payout.
i don't know