backlog

Short definition from Wiktionary

Noun

1. 1
   A large log to burn at the back of a fire.
2. 2
   A reserve source or supply.
3. 3
   An accumulation or buildup, especially of unfilled orders, unconsumed products or unfinished work.
4. 4
   A log containing text previously read, as in text-based video games or chat rooms.

Verb

1. 1
   To acquire something as a backlog, or to become a backlog