What does backlog mean?
A backlog is an accumulation of work — orders, requests, tasks, or correspondence — that has built up faster than it can be completed and now awaits attention. The term appears constantly in business and administration: companies speak of backlogs of unfilled orders, courts of pending cases, and software teams of product backlogs listing features yet to be built. In modern project management, particularly Agile and Scrum methods, the backlog has been reframed from a symptom of falling behind into a deliberate, prioritized to-do list. The word carries a mildly negative connotation when it grows unchecked, since a swelling backlog implies delays and unmet demand, but clearing one is often framed as an achievement. Less commonly, backlog can denote a stock of goods held in reserve, reflecting its original sense: logs stacked at the back of a fireplace, ready to feed a fire. This homely origin makes the word's journey to corporate jargon all the more striking.
nounAn accumulation of unfinished work, orders, or tasks that has built up and awaits completion. It can also refer to a reserve of stored things, such as logs piled up for future use.
- An accumulation of uncompleted work, tasks, or orders that needs to be dealt with.
- A large stock of something stored or kept in reserve (originally, logs stacked behind a hearth).
"The shipping delay left the company with a backlog of unfulfilled orders stretching into next month."
"After the holidays, the support team faced a daunting backlog of customer emails."
"The agency cleared its design backlog before taking on any new clients."
Standard pluralization applies.
"The department inherited several backlogs from previous administrations."
"Backlog" literally began as a pile of logs stacked at the back of a fireplace — your overflowing email inbox is named after firewood.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of backlog
Backlog originated in American English in the late seventeenth century as a literal term: a 'back log' was a large log placed at the back of a hearth to keep a fire burning overnight. From this concrete sense developed a figurative one — by the nineteenth century the word came to mean an accumulation of work awaiting completion, much as logs accumulated at the back of a fire. The word derives simply from English 'back' plus 'log', with no deeper classical root; related words are therefore other compounds and derivatives of 'log' rather than cognates from Latin or Greek.
Related word forms
How backlog is actually used
Common in business, administrative, and software-development contexts (where 'backlog' is a standard term for prioritized pending tasks, as in Agile/Scrum methodology). The word is neutral to slightly negative — a backlog usually signals falling behind, but in project management it can be a neutral planning tool.
Easily confused with backlog
A logjam is a specific blockage or impasse that halts progress entirely, whereas a backlog is simply accumulated work waiting to be done.