backlog

American  

[bak-lawg, -log] / ˈbækˌlɔg, -ˌlɒg /

noun

1. a reserve or accumulation, as of stock, work, or business.

   a backlog of business orders.

   Synonyms:

   reservoir, cache, fund, store, stock, supply

2. a large log at the back of a hearth to keep up a fire.

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verb (used with object)

backlogged, backlogging

1. to hold in reserve, as for future handling or repair.

2. to enter and acknowledge (an order) for future shipment.

verb (used without object)

backlogged, backlogging

1. to accumulate in a backlog.

   Orders are starting to backlog faster than we can process them.

backlog British  

/ ˈbækˌlɒɡ /

noun

1. an accumulation of uncompleted work, unsold stock, etc, to be dealt with

2. a large log at the back of a fireplace

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Etymology

Origin of backlog

First recorded in 1675–85; back ¹ + log ¹

Explanation

When you have extra work to do that keeps accumulating, you have a backlog. Sometimes people stay late at their jobs to take care of a backlog. A backlog of tasks might slow down an ordinary day at an office or store, or require workers to come in on the weekend to catch up. In 1680, a backlog meant "a large log placed at the back of a fireplace," and by the 1880s it came to also mean "something stored for later use." It wasn't until the early 20th century that a backlog most often referred to "extra unfulfilled orders."

Example Sentences

The backlog of afflictions in the waiting room include severe sunburn…

From The Wall Street Journal • Apr. 17, 2026

Insatiable demand for compute has boosted CoreWeave’s revenue backlog and sent the stock up 66% since the beginning of the year.

From MarketWatch • Apr. 16, 2026

New Glenn could launch again as soon as Friday, a flight set to carry a satellite developed by Texas-based AST SpaceMobile, which would help Blue Origin chip away at a yearslong backlog of orders.

From The Wall Street Journal • Apr. 15, 2026

The use of hotels to accommodate asylum seekers increased dramatically in 2020, driven by a backlog in processing asylum claims and a lack of long-term housing.

From BBC • Apr. 14, 2026

The posters were so good that word of mouth spread, and soon Lori had such a backlog of orders that she was up working until one or two every morning.

From "The Glass Castle" by Jeannette Walls

Related Words

• inventory
• stockpile