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1. A central cohesive source of support and stability
   - anchor, mainstay, keystone, linchpin, lynchpin
    
2. Fortitude and determination
   - grit, guts, moxie [N. Amer], sand, gumption, cojones [N. Amer]
    
3. The series of vertebrae forming the axis of the skeleton and protecting the spinal cord
   - spinal column, vertebral column, spine, 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
   - spine
    
5. The part of a network that connects other networks together
   "the backbone is the part of a communication network that carries the heaviest traffic"

Derived forms: backbones

Type of: connecter, connection, connective, connector, connexion [Brit], fortitude, part, portion, skeletal structure, support

Part of: axial skeleton, book, mesh, meshing, meshwork, net, network, volume

Encyclopedia: Backbone