English Dictionary

spark plug

noun

The part of an internal combustion engine which forms a high-voltage electric spark which ignites the fuel-air mixture to begin the power stroke.

I need to replace the spark plug in my car.

意味（1）

The part of an internal combustion engine which forms a high-voltage electric spark which ignites the fuel-air mixture to begin the power stroke.

With all engines using spark plugs it is comparatively easy to ascertain whether the ignition system is working properly.

意味（2）

(figuratively) Someone who is a driving force in new endeavours.

Steve Pincus, a Madison-area farmer who sells produce to L'Etoile, says admiringly of Odessa: She's a spark plug. She's out there speaking out about sustainable agriculture and local food.

意味（3）

(military) A rod (for cylindrical secondaries) or sphere (for spherical secondaries) of fissile material at the center of the secondary of a multistage thermonuclear weapon, which undergoes nuclear fission when compressed to supercriticality by the imploding secondary, helping to raise the secondary to the pressures and temperatures necessary to ignite nuclear fusion in the secondary's fusion fuel.