- The definition of back up means someone or something that is a substitute or reinforcement.
An example of back up is a second team of Navy Seals waiting to raid a compound if the primary team needs assistance.
- Back up is defined as to walk, drive or move in reverse.
An example of back up is for a truck to move in reverse to line up with a loading bay.
- Back up means to copy or save computer data on a location other than your main computer hard drive.
An example of back up is when you copy your pictures to a CD.
(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.
- That beeping sound indicates that the truck is backing up.
- (idiomatic) To move a vehicle backwards.
- Back up the car a little, you're blocking the driveway.
- (idiomatic, intransitive) To undo one's actions.
- 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) To copy (data) as a security measure.
- Back up your documents folder before applying the update.
- (idiomatic) To provide support or the promise of 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.
- (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.
- When I flushed the toilet, the plumbing backed up and burst.
back up - Computer Definition
back up - Investment & Finance Definition
A term used in the fixed-income market when prices fall and yields rise. Another use for this term occurs when an investor moves funds from a five-year note and puts them into a two-year note. This term is also used to refer to a market that reverses an upward trend and backs up.