to back order
01
to request or take an order for a product that is not currently in stock, to be delivered when it becomes available
例子
The customer back-ordered the popular laptop until the next shipment arrived.
They back-ordered the book and received it a week later.
Back order
01
缺货订单，补货中
a situation where a product is temporarily out of stock but can be ordered for future delivery
例子
My phone case is on back order, so I'll have to wait a bit longer.
我的手机壳处于延期交货状态，所以我得再等一会儿。
Due to high demand, the product is frequently on back order.
由于需求旺盛，该产品经常处于缺货预订状态。
