spark plug

• POS: Noun Phrase

CIDE DICTIONARY

spark plug,  

 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.  [Webster 1913 Suppl.]

THESAURUS

spark plug

abettor, activator, actuator, animator, arouser, cajoler, coax, coaxer, encourager, energizer, firer, gadfly, galvanizer, human dynamo, impeller, inducer, inspirer, life, motivating force, motive power, mover, moving spirit, persuader, pleader, prime mover, prompter, restorative, spark, sparker, stimulant, stimulator, stimulus, tempter, tonic, wheedler