spark plug

spark plug

noun

Definition of SPARK PLUG

1

: a part that fits into the cylinder head of an internal combustion engine and carries two electrodes separated by an air gap across which the current from the ignition system discharges to form the spark for combustion

2

: one that initiates or gives impetus to an undertaking

— spark·plug \ˈspärk-ˌpləg\ transitive verb

First Known Use of SPARK PLUG

1903

Rhymes with SPARK PLUG

bear hug, bedbug, billbug, debug, earplug, firebug, fireplug, goldbug, humbug, june bug, lovebug, prayer rug, sea slug, smart drug, stinkbug, throw rug, unplug, wall plug