obstinacy

/ˈɑbstɪnəsi/
noun
  1. The quality of being stubborn or refusing to change one's opinion or actions, even when it would be reasonable to do so.
    • Despite the evidence, his obstinacy prevented him from admitting he was wrong.
    • Her obstinacy in refusing to ask for directions made the trip much longer.
    • The child's obstinacy during the argument frustrated his parents.
  2. The quality of being difficult to remove, control, or deal with; persistence.
    • The obstinacy of the cold weather surprised everyone in April.
    • The team faced the obstinacy of the old lock, which wouldn't open with any key.
    • The obstinacy of the stain required several washes to remove.