What Does Pre- Order Mean?

verb
verb: pre-order
  1. 1.
    order (an item of merchandise) before it is available, with the understanding that it will be shipped later.
noun
noun: pre-order
  1. 1.
    an order for an item that has not yet been made commercially available.
 Please reference description of "Pre-Order" item or "Pre-Order" warning box before checkout to see when your item will be shipped