Definitions of backbone
  1. noun
    the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
    synonyms: back, rachis, spinal column, spine, vertebral column
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    a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates
    backbone of an animal
    a notochord of a larval tunicate typically confined to the caudal region
    type of:
    skeletal structure
    any structure created by the skeleton of an organism
  2. noun
    a central cohesive source of support and stability
    synonyms: anchor, keystone, linchpin, lynchpin, mainstay
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    type of:
    something providing immaterial assistance to a person or cause or interest
  3. noun
    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
    synonyms: spine
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    type of:
    part, portion
    something less than the whole of a human artifact
  4. noun
    the part of a network that connects other networks together
    “the backbone is the part of a communication network that carries the heaviest traffic”
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    type of:
    connecter, connection, connective, connector, connexion
    an instrumentality that connects
  5. noun
    fortitude and determination
    synonyms: grit, gumption, guts, moxie, sand
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    type of:
    strength of mind that enables one to endure adversity with courage
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