A person who flouts; someone who deliberately disregards or shows contempt for rules or authority.
From 'flout' plus the agent suffix '-er'; formed in the 1600s to describe someone habitually engaged in flouting.
Calling someone a 'flouter' is much harsher than saying they 'broke a rule'—it emphasizes that they're the type of person who actively mocks and disrespects authority itself.
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