Backup

/bˈækʌp/

/ˈbæˌkəp/

Backup

the act of providing assistance or support to someone or something

synonyms : backing

(computing) a copy of computer data that can be used to restore lost or damaged data

a musical part (vocal or instrumental) that supports or provides background for other musical parts

someone who takes the place of another (as when things get dangerous or difficult)

synonyms : backup man

an accumulation caused by clogging or a stoppage

Examples

1. The alarm clock has a backup battery in case of a power outage.

2. She's a backup dancer for a famous pop singer.

3. She's joining the pop star's tour as a backup singer.

4. The backup quarterback had to make up for the injured starter and lead the team to victory.