interrupter

noun
  1. A person or thing that interrupts or causes an interruption. noun
    The loud noise from the construction site was an unwelcome interrupter during the meeting.
    As an interrupter, he often disrupted the flow of conversation with his frequent comments.
  2. A device or mechanism that interrupts an electrical circuit, often used for safety purposes. noun
    The circuit interrupter tripped, cutting off the power to prevent an overload.
    Installing a ground fault circuit interrupter can help prevent electrical shocks in wet areas.