Stubborn and unyielding; refusing to listen to reason or accept different viewpoints; also pragmatic and realistic rather than emotional.
Compound of 'hard' (Old English 'heard') and 'headed' (from 'head'). The metaphor uses physical hardness to represent mental inflexibility, dating back to Middle English.
Interestingly, 'hardheaded' is complimentary in business contexts (it means you're rational and won't be scammed) but negative in relationships (it suggests you won't compromise or listen)—same word, total opposite vibe.
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