backbone

(n) 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
keystone, linchpin, lynchpin, anchor, mainstay,
(n) fortitude and determination
- he didn't have the guts to try it
guts, moxie, grit, gumption, sand,
(n) the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
- the fall broke his back
spinal column, spine, vertebral column, rachis, back,
(n) 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
- the title and author were printed on the spine of the book
spine,
(n) the part of a network that connects other networks together
- the backbone is the part of a communication network that carries the heaviest traffic

keystone linchpin lynchpin anchor mainstay guts moxie grit gumption sand spinal column spine vertebral column rachis back