Spark plug

1.

In internal-combustion engines with electric ignition, a plug, screwed into the cylinder head, connected with the induction coil or magneto circuit on the outside, and used to produce a spark to ignite the fuel-air mixture in the engine.

Noun

1.

spark plug - electrical device that fits into the cylinder head of an internal-combustion engine and ignites the gas by means of an electric spark Synonyms: sparking plug, plug

electrical device, ignition, ignition system, plug, sparking plug