alternative order means: This is used in the context of all equities. A broker can choose between buying or selling, but not both. The execution of any one of these courses automatically removes the other. A combination buy limit and stop order is an example. The buy limit must be below the market, while the stop can be above. When one trading unit is ordered, an order for the second option is cancelled. The amount of an order for more than one unit is determined by the executions. Also known as “One Cancels the Other”. You can also see Either-or. (in Stock Market Dictionary)