A miscreant is someone who behaves badly or does wrong things, especially someone who breaks rules or causes trouble on purpose. The word carries a sense of real wrongdoing, such as serious offenses like theft, bullying, or deliberate harm. A student who occasionally talks during class is being disruptive, but someone who repeatedly steals from lockers or bullies others might be called a miscreant.

You might encounter miscreant in older adventure stories, where the hero defeats a band of miscreants terrorizing a village, or in historical accounts describing outlaws and wrongdoers.

Today the word sounds somewhat old-fashioned and formal. You're more likely to see it in writing than hear it in everyday conversation. When someone does use it, they're often being a bit dramatic or literary, choosing a fancier word instead of simply saying “troublemaker” or “criminal.” A teacher might jokingly call a prankster a “young miscreant,” adding humor through the contrast between the serious-sounding word and the relatively minor misbehavior.