spark plug


: 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
: one that initiates or gives impetus to an undertaking
sparkplug transitive verb

Examples of spark plug in a Sentence

Recent Examples on the Web As electric vehicle markets grow, what will happen to makers of engine blocks, spark plugs, radiators, transmissions, castings and the rest of our gasoline engine supply chain? Kathleen Gallagher, Journal Sentinel, 14 June 2024 Linklater’s spark plug of a romantic thriller/comedy, which cleverly springboards off the real-life exploits of fake assassin Gary Johnson (embellishing on them, of course). Randy Myers, The Mercury News, 5 June 2024 Motorcyclists can bring their bike to their local dealers to replace all four spark plugs for free. USA TODAY, 1 Apr. 2024 Known as a lockdown defender, spark plug, and slasher, Folkes has attempted just 19 free throws on the season, connecting on just 37%. Hunter Bailey, Charlotte Observer, 7 Mar. 2024 See all Example Sentences for spark plug 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'spark plug.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1903, in the meaning defined at sense 1

Time Traveler
The first known use of spark plug was in 1903

Dictionary Entries Near spark plug

Cite this Entry

“Spark plug.” Dictionary, Merriam-Webster, Accessed 25 Jun. 2024.

Kids Definition

spark plug

: a device used in an engine to produce a spark that ignites a fuel mixture
: one that begins something or drives something forward

More from Merriam-Webster on spark plug

Last Updated: - Updated example sentences
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