backup

play
noun, often attributive back·up \-ˌəp\

Definition of backup

  1. 1a :  one that serves as a substitute or support <I brought an extra pencil for backup.> <a backup plan>b :  musical accompaniment <The tunes include banjo and guitar backup.>c :  additional personnel who provide assistance <The police officer called for backup.>

  2. 2 :  an accumulation caused by a stoppage in the flow <traffic backup>

  3. 3 :  a copy of computer data (as a file or the contents of a hard drive) <I made a backup copy of the file.>; also :  the act or an instance of making a backup

Examples of backup in a sentence

  1. His role on the team is to be a backup to the regular quarterback.

  2. We have an extra radio as a backup in case this one doesn't work.

  3. We have an extra radio for backup.

  4. He provides backup for the regular quarterback.

  5. She sang backup on his CD.

1910

First Known Use of backup

1910


BACKUP Defined for English Language Learners

backup

play
noun, often attributive back·up \-ˌəp\

Definition of backup for English Language Learners

  • : a person or thing that can be used to replace or support another person or thing

  • : help or support provided by additional people or things

  • : a situation in which the flow of something (such as traffic) becomes blocked


BACKUP Defined for Kids

backup

play
noun back·up \ˈbak-ˌəp\

Definition of backup for Students

  1. :  a person who takes the place of or supports another <The guard called for a backup.>



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