dynamo
/ˈdʌɪnəməʊ
/noun (plural dynamos) chiefly British
1A machine for converting mechanical energy into electrical energy, typically by means of rotating coils of copper wire in a magnetic field.A dynamo converts mechanical energy from a moving electrical conductor into electromagnetic energy and thus generates current....
- Arguably the autocar laid the foundations for many of today's trains - using a petrol engine to drive a dynamo to power electric motors.
- When he walks, the rotor of the dynamo rotates generating electricity and rechargeable batteries could be charged.
1.1 informal An extremely energetic person: she was a dynamo in London politics...
- The four organizers of Expozine are dynamos of productivity.
- She was always a little dynamo, more than willing to jump in and lend a hand, always had a smile on her face.
- She is an intellectual dynamo and long-time friend.
Origin
Late 19th century: abbreviation of dynamo-electric machine, from Greek dunamis 'power'.