back up

To make an extra copy of computer files in case the original files are lost.

• Always back up your files.
• I backed up my photos last night.
• Does this program back everything up automatically?

How to use it: back something up (Remember to back your files up.); back something up to something (I back my photos up to an external drive.)

Similar words: make a backup, copy

Common phrases: back up files, back up data, back up photos

To move backwards, especially in a car or other vehicle.

• Please back up a little.
• The truck backed up towards the gate.
• Can you back up without hitting the fence?

Similar words: reverse, move backwards

Opposites: advance

Common phrases: back up slowly, back up carefully

To support someone or help show that a statement is true.

• Will you back me up?
• Her friends backed her up during the argument.
• The report backs up our claims with clear evidence.

How to use it: back someone/something up (The witnesses backed her story up.); back something up with something (He backed his claim up with photographs.)

Similar words: support, stand by, confirm

Opposites: oppose

Common phrases: back up someone, back up claims, back up something

To make a car or other vehicle move backwards.

• Please back up the car.
• He backed the truck up to the loading bay.
• Can you back it up another metre?

How to use it: back something up (She backed the van up carefully.); back up something (Please back up the car a little.)

Similar words: reverse

Common phrases: back up something, back up vehicles

To undo earlier steps so you can try a different way.

• We need to back up and start again.
• I backed up two steps and tried a different method.
• They backed up to the last working version and rebuilt the page.

Similar words: go back, retrace your steps

Common phrases: back up again, back up first

To return to an earlier point in your thinking and consider it again.

• Let us back up and think again.
• She backed up and questioned her first idea.
• Before we decide, can we back up and consider the problem?

Similar words: rethink, reconsider

Common phrases: back up briefly, back up mentally