backbone

/ˈbækˌboʊn/
noun
  1. The series of bones (vertebrae) that runs down the middle of the back; the spine.
    • She injured her backbone in a fall and had to wear a brace.
    • The human backbone protects the spinal cord and supports the body.
    • A healthy backbone is essential for good posture.
  2. The main support or most important part of a system, organization, or structure.
    • Volunteers form the backbone of the charity's operations.
    • Small businesses are the backbone of the local economy.
    • The internet's backbone consists of high-speed cables that connect continents.
  3. Strength of character; courage and determination.
    • It takes backbone to stand up for what you believe in.
    • He showed real backbone by admitting his mistake publicly.
    • She has the backbone to lead the team through difficult times.
Antonyms
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