backup
BAK-uhp
Backup (noun) means a person, plan, or system kept in reserve in case the main one fails. Example: “The pilot switched to the backup system when the main engine failed.”
noun
1
A person, plan, or system kept in reserve in case the main one fails.
"The pilot switched to the backup system when the main engine failed."
"Always bring a backup charger when you travel."
"The understudy served as backup in case the lead actress got sick."
2
A copy of digital files kept separately so the originals can be restored if lost or damaged.
"Make a backup of your files before you update the software."
"The company restores its data from a nightly backup whenever a server crashes."
"She lost her laptop, but luckily she had a backup of all her photos in the cloud."
3
A buildup or blockage that stops something from flowing normally, such as traffic or plumbing.
"A backup in the kitchen sink meant the water would not drain away."
"Roadworks caused a long backup of cars at the roundabout this morning."
"There was a serious backup on the highway after the accident."
How to use backup
Learner’s notesIn plain EnglishSomething held in reserve for support, or a saved copy of data, or a jam that stops normal flow.
Common pairings
backup plan
backup files
traffic backup
call for backup
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Word forms
- Plural
- backups
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The pilot switched to the _____ system when the main engine failed.
Etymology
A noun formed from the phrasal verb back up, meaning to support or reinforce from behind.
Synonyms
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Frequently asked questions
What does “backup” mean?
The word “backup” means a person, plan, or system kept in reserve in case the main one fails. In plain terms, something held in reserve for support, or a saved copy of data, or a jam that stops normal flow.
How do you pronounce “backup”?
“Backup” is pronounced BAK-uhp (/ˈbækˌʌp/ in IPA).
How do you use “backup” in a sentence?
Here is “backup” used in a sentence: “Always bring a backup charger when you travel.”
What is another word for “backup”?
Words with a similar meaning to “backup” include reserve and spare.
What part of speech is “backup”?
“Backup” is a noun.
Is “backup” a common word?
“Backup” is a fairly common word in modern English, usually learned at around the B2 level.
How many meanings does “backup” have?
“Backup” has 3 distinct senses listed in this dictionary. The most common is: a person, plan, or system kept in reserve in case the main one fails.
What is the difference between 'backup', 'back up', and 'back-up'?
'Backup' as one word is a noun or adjective, as in 'make a backup' or 'a backup plan'. 'Back up' as two words is the verb, as in 'back up your files'. The hyphenated 'back-up' is an older or British variant of the noun, though the single word is now most common.
What is the difference between a 'backup' and an 'archive'?
A 'backup' is a copy of digital files kept separately so the originals can be restored if lost or damaged, and it is usually meant to be current and recoverable. An 'archive' is long-term storage of older files that are no longer in active use but kept for records, so a backup restores what you use now while an archive preserves the past.
What words commonly go with 'backup'?
In the 'reserve' sense, 'backup' often appears in 'backup plan', 'backup singer', and 'call for backup'. In the digital sense, it pairs with verbs such as 'create a backup', 'restore from a backup', and 'automatic backup'.
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