One who attitudinises; a person who adopts exaggerated attitudes or affected poses.
From attitudinise + -r (agent suffix forming nouns for people who do something). British English variant; the American form would be 'attitudinizer.'
In the 1800s, calling someone an 'attitudiniser' was the polite intellectual's way of saying 'fake,' implying they had training (perhaps in acting or philosophy) but used it for hollow effect rather than genuine expression.
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