back up

British  

verb

1. (tr) to support or assist

2. (intr) cricket (of a nonstriking batsman) to move down the wicket in readiness for a run as a ball is bowled

3. (of water) to accumulate

4. (of traffic) to become jammed behind an accident or other obstruction

5. computing to make a copy of (a data file), esp for storage in another place as a security copy

6. printing to print the second side of (a sheet)

7. to repeat an action immediately

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noun

1. a support or reinforcement

2. 1. a reserve or substitute

   2. ( as modifier )

      backup troops

3. 1. musical accompaniment, esp for a pop singer

   2. ( as modifier )

      backup singer

4. the overflow from a blocked drain or pipe

5. computing a file or set of files copied for security purposes

back up Idioms  

1. Move or drive a vehicle backward, as in He told her to back up into the garage . [First half of 1800s]

2. Bring or come to a standstill, as in The water had backed up in the drains , or The accident had backed up traffic for miles . [First half of 1800s]

3. Support or strengthen, as in The photos were backed up with heavy cardboard so they couldn't be bent , or I'll back up that statement of yours . [Second half of 1700s]

4. Duplicate a file or program so that the original is not lost. For example, Every computer manual warns you to back up your work frequently in case of a power outage or computer failure . [Second half of 1900s]

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Example Sentences

See Examples For:

back up

"I'm hoping we'll get a good reaction when the prices go back up in September and people will be understanding of that," she added.

From BBC ● Jul. 27, 2026

He just laughed, got back up and got in position for the next rep.

From Los Angeles Times ● Jul. 25, 2026

Oil prices have shot back up since the end of the ceasefire, which affects a lot more than the price of gasoline.

From Slate ● Jul. 25, 2026

BPC-157: It is well-known to peptide enthusiasts — and one of the few to have at least one study conducted in humans that appears to back up some of the claims for its benefits.

From MarketWatch ● Jul. 23, 2026

Was that evidence strong enough to back up my claim?

From "Not Nothing" by Gayle Forman

Related Words

• fall back
• retreat