dynamo

/ˈdaɪnəmoʊ/
noun
  1. A machine that produces electricity by converting mechanical energy, especially one that uses a coil of wire turning in a magnetic field.
    • The old bicycle had a small dynamo that powered the headlight.
    • Engineers installed a dynamo in the dam to generate electricity for the village.
    • When the power went out, the emergency dynamo kicked in to keep the hospital running.
  2. A person who is very energetic, active, and hardworking.
    • Even at 70, he's a dynamo on the tennis court, running faster than players half his age.
    • My grandmother is a real dynamo; she gardens, volunteers, and still finds time to bake.
    • The new manager is a dynamo who has already doubled the team's productivity.
Antonyms