back up
bak UP
/bæk ʌp/
To provide support or evidence for a claim or a person.
Essential for arguments and academic writing.
The story behind the word. From the military concept of 'backup' troops who stay behind the front line to provide support if needed. You are standing 'at the back' of someone to keep them from falling.
Word relationships
- substantiate: 'Substantiate' is much more formal.
- contradict: To say the opposite of what someone else has said.
Commonly confused with
- support: 'Support' is broader; 'back up' specifically implies providing the evidence or the 'rear' strength.
Word family
- backup (noun): Support or help; a copy of data.
Collocations
- back up a claim
- back up an argument
- back someone up
Example sentences
- "You need to back up your theories with hard data." A scientific argument.
- "If you tell the boss about the problem, I'll back you up." Supporting a colleague.
Memory hook
Imagine standing behind a friend to catch them if they trip. The strength behind the words.
When not to use
Don't confuse with the literal 'back up' (moving a car in reverse) or 'back up' (making a copy of computer files).
Fun facts
- In the 18th century, 'back up' was used in sports to mean supporting a teammate.
Related words
Explore more words
substantiate, buttress, corroborate, bolster, endorse, affirm
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