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definitions

back order

noun
  1. Commerce. an order or part of an order waiting to be filled.

back-order

[bak-awr-der]
verb (used with object)
  1. to treat as a back order: We have to back-order your sofa until the new fabric arrives.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Word Origin and History for backorder

also back-order, by 1980 (n.); 1985 (v.), from back (adj.) + order. Related: Backordered.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with backorder

back order

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.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.