vigilante

باللغة العربية: مُطَبِّقُ القَانُونِ بِيَدِهِ، حَارِسٌ أَهْلِيّ

1. A member of a vigilance committee.
2. A person who acts outside of legal authority, often violently, to punish or avenge a crime, right a perceived wrong, etc.

الجمع vigilantes