A stubborn, obstinate person who refuses to listen to others or change their mind easily.
Compound of 'hard' and 'head', using the metaphor of a solid, unchangeable skull to represent mental inflexibility. The term has been used since at least the 16th century to describe obstinate individuals.
Interestingly, 'hardhead' has been used both as an insult and as praise depending on context—sometimes stubbornness is exactly what you need to persist through impossible odds.
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