RhymeZone: backup definitions

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)