back bone

名词 back bone:

1. a central cohesive source of support and stability
   同义词：anchor, mainstay, keystone, backbone, linchpin, lynchpin
2. fortitude and determination
   同义词：backbone, grit, guts, moxie, sand, gumption
3. the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
   同义词：spinal column, vertebral column, spine, backbone, back, rachis
4. the part of a book's cover that encloses the inner side of the book's pages and that faces outward when the book is shelved
   同义词：spine, backbone
5. the part of a network that connects other networks together
   同义词：backbone