Definitions of backup:
- noun: (computer science) a copy of a file or directory on a separate storage device
Example: "He made a backup in case the original was accidentally damaged or erased"
- noun: an accumulation caused by clogging or a stoppage
Example: "A traffic backup on the main street"
- noun: the act of providing approval and support
- noun: a subordinate musical part; provides background for more important parts
- noun: someone who takes the place of another (as when things get dangerous or difficult)
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