If you sell an option, you can set a buy-stop order. If the stock trades at that price or higher, the options are bought at the market price, limiting losses. ... You may prefer that the option must trade at, or through, your limit price. That's how a stop-loss order is triggered when trading stock. stop-loss order is essentially an automatic trade order given by an investor to his or her brokerage – only be executed once the price of the stock in question falls to the specified stop price stated in the investor's stop-loss order. Such orders are designed to limit an investor's loss on a position in a security. thanks