- Commerce. an order or part of an order waiting to be filled.
- to treat as a back order: We have to back-order your sofa until the new fabric arrives.
An item not currently in stock but to be sold or delivered when it becomes available, as in We don't have the shoes in white, but we can make them a back order. The verb back-order means “to obtain such an item,” as in The furniture store is going to back-order the sofa for us.