backup
英 ['bækʌp]
美['bæk,ʌp]
	    - n. 支持;后援;阻塞
 - adj. 支持的;候补的
 - vt. 做备份
 
英英释意
- 1. an accumulation caused by clogging or a stoppage;
 - "a traffic backup on the main street"
 - "he discovered a backup in the toilet"
 
- 2. someone who takes the place of another (as when things get dangerous or difficult);
 - "the star had a stand-in for dangerous scenes"
 - "we need extra employees for summer fill-ins"
 
- 3. a subordinate musical part; provides background for more important parts
 
- 4. (computer science) a copy of a file or directory on a separate storage device;
 - "he made a backup in case the original was accidentally damaged or erased"
 
- 5. the act of providing approval and support;
 - "his vigorous backing of the conservatives got him in trouble with progressives"