to back

'to back away from' something or someone means to retreat or move backwards from something, usually slowly, because you are frightened of them.

• When I saw the snake, I slowly backed away from it and called for help.
  
• He tried to back away from the man with the knife but was trapped.
  

'to back away from' an idea or suggestion means to disassociate yourself from it and not support it.

• He was going to say yes to the proposal but then backed away from it and didn't.
  
• He backed away from plans for a vote of no confidence.
  

'to back down' means to admit that you were wrong or that you have been defeated.

• When he was confronted with the facts, he quickly backed down.
  
• He wouldn't back down. He maintained his position in spite of all the evidence.
  

'to back off' means avoiding a difficult situation by not becoming involved in it.

• Let me deal with this. Just back off .
  
• At first she was very aggressive but then she backed off.
  

'to back onto' describes how the back of a house or building faces in a specific direction.

• The house backs onto the river. We have a lovely view.
  
• The building backs onto the car park in the city centre.
  

'to back out' means to withdraw from an agreement that has been made.

• He is no longer going to pay the amount we agreed. He has backed out of our agreement.
  
• We were going to go on holiday together but then he backed out at the last minute.
  

'to back out' your car means to reverse it from a place or position.

• I broke the mirror backing out of the parking lot.
  
• It is illegal to back out of your garden on to the road.
  

'to back up' means to give an idea support or to prove it.

• He had figures from some very reliable sources to back up his arguments.
  
• He didn't have any receipts to back up his insurance claim after the burglary.
  

'to back up' also means to make a copy of something in case the original is damaged, especially on the computer.

• Before you start installing new software, back up your files.
  
• I have to back up my work regularly so that I don't lose it if the computer goes down.
  

'to back someone up' means to support or to help them.

• That's exactly what happened. The others will back me up.
  
• Nobody backed me up. I was left alone to defend myself against the criticism.
  

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