# back up
## English
### Pronunciation

* Audio (General Australian):(file)
* Audio (General American):(file)

### Verb

back up (third-person singular simple present backs up, present participle backing up, simple past and past participle backed up)
* (idiomatic, intransitive) To move backwards, especially for a vehicle to do so.
    Coordinate terms: back away, back off, stand back
    That beeping sound indicates that the truck is backing up.
** 1897 December (indicated as 1898), Winston Churchill, chapter V, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd., →OCLC:We expressed our readiness, and in ten minutes were in the station wagon, rolling rapidly down the long drive, for it was then after nine. […] As we reached the lodge we heard the whistle, and we backed up against one side of the platform as the train pulled up at the other.
* (idiomatic, transitive) To move a vehicle backwards.
    Synonym: reverse
    Hyponym: back out
    Back up the car a little, you're blocking the driveway.
* (idiomatic, intransitive) To undo one's actions.
    Synonym: back out
    I couldn't see how to finish the project, so I backed up and tried it another way.
* (idiomatic, intransitive) To reconsider one's thoughts.
    This isn't working. Let's back up and think about it.
* (idiomatic, computing, transitive) To copy (data) so that it can be restored if the main copy is lost.
    Back up your documents folder before applying the update.
* (idiomatic, transitive) To provide support or the promise of support to.
    Synonyms: back, support
    You should be careful. This guy is backed up by the local gang.
    When he said I wasn't there, I told him I was, and my buddy backed me up.
** 2017, BioWare, Mass Effect: Andromeda (Science Fiction), Redwood City: Electronic Arts, →OCLC, PC, scene: Update on Jaal:Thank you for backing me up. I know it's not easy delivering bad news-especially to a friend-but sometimes it's the only way we can move forward and begin to heal.
** 2020 May 6, Tim Dunn, “The Architecture The Railways Built”, in Rail, page 76:Researching and corroborating facts to put in my script is one thing, but getting sources to back up the assertions of interviewed contributors can be quite another.
* (idiomatic, intransitive, cricket) For the non-striker to take a few steps down the pitch, in preparation to taking a run, just as the bowler bowls the ball.
* (idiomatic, intransitive, cricket) For a fielder to position himself behind the wicket (relative to a team-mate who is throwing the ball at the wicket) so as to stop the ball, and prevent overthrows.
* (idiomatic, intransitive, of a blockage) To halt the flow or movement of something.
    Synonym: plug up
    When I flushed the toilet, the plumbing backed up and burst.
* (idiomatic, intransitive, informal) To fill up because of a backlog.
    Synonym: fall behind
** 1995, "Oubliette" (episode of The X-Files TV series)
    WAITRESS: Hurry up with those drinks, Lucy. We're backing up. (Grabs the drinks LUCY has poured.) What are you doing? These are regular. They all ordered large.
* (obsolete, printing) To run a printing press in reverse.

#### Derived terms

* backupable

#### Translations
### See also

* back down
* back into
* back off
* back out

### Anagrams

* upback