Also known as Down Bet.
Spread betting term, meaning that you are betting that the lower value of a spread betting quote will not be reached.
For example, Flintoff is quoted for 50-55 runs. You think he is out of form and Sell at 50. If he is out for 15 you win (50-15) x £stake. But if bats well and hits 75 then you lose (75-50) x £stake. In these cases if you staked £1 you win £35 in the first and lose £25 in the second.
See also Buy.