backup

Everyday

1. An extra copy of computer files kept safe in case the first copy is lost. tree →
2. Extra help or support, such as more police or players who can join when needed. tree →
3. Something kept ready in case the first plan fails, like a backup plan. tree →
4. (US) A traffic jam or a blockage, such as a sink backup. tree →

In the lessons

In computing lessons pupils learn to make a backup of their work. In everyday life and safety it means having a second plan or extra help. In stories police "call for backup". Phrases: "make a backup", "backup plan", "call for backup", "back up your files", "back someone up" (support them).

Examples

• Always make a backup of your homework on a memory stick. tree →
• My laptop broke, but I had a backup in the cloud. tree →
• If it rains, our backup plan is the cinema. tree →
• The officer called for backup. tree →
• The backup goalkeeper came on in the second half. tree →
• Please back up your files before the update. tree →
• My friend backed me up when I told the truth. tree →
• There was a backup of cars on the motorway. tree →

Note

Written as one word "backup" for the noun and adjective, but as two words "back up" for the verb: "I back up my files" and "I have a backup". Countable: a backup, two backups.