Alternative Order
  
Think of an alternative order as an either-or instruction to a broker. So you'll give your broker two options and if one of the options is executed, then the other order is immediately cancelled. As in “do one or the other of these, but for goodness sake DON’T DO BOTH!!!!”
It's like if your friend says he'd like to go to either Arby's or Taco Bell. Either one might be fun, but going to both probably points to a long night spent sitting on the modern day phone booth. In practical terms, an alternative order might go something like this: "either buy shares for New Tech Co. if it reaches $10 per share, or buy shares of Old-Tyme Car Maker Inc. if it hits $15 per share." The broker will then buy whichever stock hits its target first, then ignore the other option.