back-up的英文翻译是什么意思，词典释义与在线翻译
名词 backup:- an accumulation caused by clogging or a stoppage
- someone who takes the place of another (as when things get dangerous or difficult)
- a musical part (vocal or instrumental) that supports or provides background for other musical parts
- (computer science) a copy of a file or directory on a separate storage device
- the act of providing approval and support
动词 back up:- give moral or psychological support, aid, or courage to
- move backwards from a certain position
- establish as valid or genuine
- make a copy of (a computer file) especially for storage in another place as a security copy
- become or cause to become obstructed
