back orderEnglishOxford Dictionary of Englishback order ▸ noun a retailer's order for a product that is temporarily out of stock with the supplier: the phone I wanted was on back order. ▸ verb [with object] (back-order) place an order for (a product) that is temporarily out of stock: the item was back-ordered by our distributor the taps can be back-ordered and take up to three months for delivery.