obduracy

/ˈɑbdərəsi/
noun
  1. The quality of being stubbornly unwilling to change one's opinion or course of action.
    • The child's obduracy in refusing to eat vegetables frustrated her parents.
    • The negotiator was surprised by the obduracy of the other side, who refused every compromise.
    • Despite all the evidence, his obduracy made him stick to his false story.