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back up

verb

Definition of back up

  1. intransitive verb
  2. :  to accumulate in a congested state <traffic backed up for miles>

  3. transitive verb
  4. 1 :  to move into a position behind (a teammate) in order to assist on a play

  5. 2 :  hold back 1

  6. 3 :  to make a copy of (a computer file or data) to protect against accidental loss; also :  to make copies of all the files on (a hard drive)



1837

First Known Use of back up

1837



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WORD OF THE DAY

of or relating to the heavens

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