“Flipper” is a term used in cricket to define a delivery bowled by leg spinners that keeps relatively low and traps batsmen in front of wicket or bowled them over. The trick behind Flippers is that it’s bowled from the front of the hand is spinning backwards as it’s approaching the batsman. With opposite spin, ball trys to return but momentum on it flicks it in forward direction and hence lack of bounce due.
Former Aussie legend Shane Warne was an artist at this delivery while Clarrie Grimmett also of Australia is known to have first discovered flipper.
Anil Kumble also used this as a weapon.