pigheaded
Very stubborn and refusing to listen or change your mind.
Pigheaded means stubbornly refusing to change your mind or consider other viewpoints, even when you're clearly wrong or when changing course would make sense. A pigheaded person digs in their heels and won't budge, no matter what evidence or reasoning others present.
Imagine a student who insists their answer is correct even after the teacher shows them the mistake in their work, or a friend who refuses to admit they took a wrong turn on a hike even as everyone gets more lost. That's being pigheaded: clinging to your position simply because it's your position, not because it's actually right.
The word combines stubbornness with a particular flavor of unreasonableness. While being determined or persistent can be admirable traits when you're working toward a goal, being pigheaded means you've crossed into foolishness. You're so focused on not backing down that you've stopped thinking clearly.
People sometimes confuse confidence with being pigheaded, but they're different. Confident people can listen to criticism and adjust when needed. Pigheaded people refuse to listen. Being pigheaded usually makes problems worse, not better, because it prevents you from learning, compromising, or finding better solutions.