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Synonyms

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. a support or reinforcement

    1. a reserve or substitute

    2. ( as modifier )

      backup troops

    1. musical accompaniment, esp for a pop singer

    2. ( as modifier )

      backup singer

  2. the overflow from a blocked drain or pipe

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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]


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

She held it, as carefully as if it were alive, and watched the needle spin a full circle, until it pointed back up the cliff, back exactly the way she had come.

From Literature

This is backed up by research from Internet Matters, which found 64% of teens are using AI chatbots for help with everything from homework to emotional advice and companionship.

From BBC

SAP also said it’ll buy back up to €10 billion in stock.

From MarketWatch

Yes, back up off the youngsters a little bit.

From Los Angeles Times

When you stop taking a statin, the cholesterol will go back up.

From The Wall Street Journal