A troublemaker is someone who causes disruption and mischief. A GADFLY is a person who annoys others by persistent criticism, while a BUSYBODY is someone who meddles in the affairs of others. A BRAT is a term used to describe an ill-mannered child, and a GOSSIP is someone who spreads rumors or hearsay. A ROGUE is a dishonest or unprincipled person, and a FIREBRAND is someone who stirs up trouble or causes unrest. A STIRRER is someone who provokes argument or discord, and a HELLION is a mischievous person. A REBEL is someone who resists authority, and a SCAMP is a mischievous person, especially a child. A GREMLIN is a mischievous imaginary creature, and an AGITATOR is someone who stirs up public feeling on a political or social issue. An IMP is a mischievous child or sprite, and a DEVIL is a wicked or evil person. A bad egg is a person with a bad character, and a MENACE is someone or something that is a threat or danger. Finally, a bad apple is a person who has a corrupting influence on others.