back up (something)

1. to make an electronic copy of information in a computer so that it can be stored separately.

We back up our files on a disk every day.

2. to state the truth of something.

The last speaker backed up what most of the other people said.

• Don't hold your breath.
• Don't make me laugh.
• don't mention it
• don't need this
• don't rock the boat
• Don't spare the horses.
• Don't sweat it!
• Don't sweat the small stuff.
• Don't take any wooden nickels.
• don't you dare
• do nut
• doom and gloom
• do one better
• do one better than
• do one better than someone
• do one better than something
• do-or-die
• door to door
• do own thing
• do part
• do proud
• dos and don'ts
• do share
• do someone any favours
• do someone a power of good