A person who emphasizes or is preoccupied with attitudes and postures; a believer in attitudinarianism.
From attitude + -ist (suffix forming nouns for adherents or practitioners). This is a rare variant form, less common than attitudinarian.
This is a delightfully obscure variant—calling someone an 'attitudist' sounds almost scholarly, as if you're critiquing a whole philosophy of fake sophistication rather than just their annoying behavior.
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