back up

phrasal verb·4 senses·particle up

Usefulness

Meanings

1

Make a digital copy of data as a safeguard

Why “up”? A person or thing receives help so they do not fall, fail, or lose something important. It can also mean accepting a burden.

Back up your files before the update.
Make copies of your files in case the originals are lost.
She backed up the photos to an external drive.
She copied the photos to an external drive so they would be safe.
Maya backed up the final presentation on the office drive.
Maya made a safe digital copy of the final presentation on the office drive.
2

Support someone's claim, story or position

Will you back me up at the meeting?
Will you publicly support me at the meeting?
I can back that up with an example: I cut API response times by 40%.
I can support what I said with an example: I reduced API response times by 40%.
The figures back up our claim.
The figures show that our claim is true.
Leo backed up Maya's claim with the project results during the office presentation.
Leo supported Maya's claim with the project results during the office presentation.
3

Move backward along the same path

Why “up”? Movement changes from forward to backward. You travel a short way along the same path in the opposite direction.

Back up slowly, there is a wall behind you.
Move backward slowly because there is a wall behind you.
The driver backed up to let the bus pass.
The driver moved backward to make space for the bus.
4

(of traffic or water)accumulate because flow is blocked

Increaseuncommon

Why “up”? More of something is higher. Quantity, intensity and speed all rise.

Traffic backed up for miles after the crash.
Traffic formed a queue for miles after the crash.
Water backed up in the kitchen sink.
Water could not drain and collected in the kitchen sink.

Don't confuse with

back upback out

Back up means make a digital copy of data as a safeguard. Back out means withdraw from a commitment or agreement.

Test yourself

Back up your files before the update. What does it mean?

Nearby in the meaning map

Sink In connects verbs by particle pattern, contrast pairs, and shared base verbs.

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Side-by-side comparisons with the verbs learners most often confuse for “back up”.

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