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

Pressed on whether he had evidence to back up the claim, he said he told family and friends at the time what had been said "because it was so monstrous".

From BBC ● Sep. 18, 2026

But tensions flared back up later in the month after disputes over alternative shipping channels and alleged U.S. bypass moves.

From MarketWatch ● Sep. 17, 2026

State-run Saudi Aramco said it was looking to get back up to full capacity in about six weeks, Bloomberg cited sources as saying.

From Barron's ● Sep. 17, 2026

And CBO assumes net immigration picks back up after its recent decline.

From The Wall Street Journal ● Sep. 13, 2026

He looked back up at the sky and was tempted to call his father again.

From "Storm Runners" by Roland Smith

Related Words

• fall back
• retreat