An options strategy created by being long in one put and two call options, all with the exact same strike price, maturity and underlying asset. Also referred to as a "triple option".
A strap option is used when a trader believes that the future price movement of the underlying security will be large and more likely up than down. By adding two call options the trader has a large gain if he or she is right about the large upward movement. But if the forecast is wrong and the price has a large reversal, the trader is protected by the put option.