1. In electronics, a choke is a coil of low-resistance wire that acts as an inductor. Chokes are used to limit the flow of high-frequency alternating current (AC) in radio circuits or to smooth the waveform of the direct current from a rectifier. A familiar choke in domestic use is the "starter" of a fluorescent lighting unit.
2. In an internal combustion engine, a choke is a mechanical valve-like device that reduces the amount of air in the air-fuel mixture in order to provide a rich enough mixture for the engine to start.