backbone
英 ['bækbəʊn]
美['bæk'bon]
	    - n. 支柱;主干网;决心,毅力;脊椎
 
英英释意
- 1. a central cohesive source of support and stability;
 - "faith is his anchor"
 - "the keystone of campaign reform was the ban on soft money"
 - "he is the linchpin of this firm"
 
- 2. fortitude and determination;
 - "he didn't have the guts to try it"
 
- 3. the series of vertebrae forming the axis of the skeleton and protecting the spinal cord;
 - "the fall broke his back"
 
- 4. the part of a network that connects other networks together;
 - "the backbone is the part of a communication network that carries the heaviest traffic"