What is the Meaning of BACK UP?

Definition 1:

If something backs up, it means the regular flow is slowed or stopped.

example 1:

Don’t pour grease down your kitchen drain or the water will back up.

example 2:

Every day the traffic on the freeway starts to back up at 4:00 p.m.

back up s.o./s.t.
back s.o./s.t. up

Definition 2:

to drive, or move, in reverse

example 1:

Could you please back your car up a little?

Note: For this definition, it is not always necessary to include the object (e.g., the car).

example 2:

Could you back up a little?  (This means back yourself up.)

Definition 3:

to support

example 1:

They had no scientific evidence to back up their claims.

example 2:

My boss doesn’t believe me. I am glad that Cris will back me up.

Definition 4:

to make a second copy of computer information and store it in a separate place, so the information is safe if there are problems with your computer

example 1:

We back up all our data every Friday.

example 2:

My computer got a virus and everything on my hard drive was destroyed. Fortunately, I had been regularly backing everything up.

 

Phrasal Verb List