spark plug


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

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Other Words from spark plug

sparkplug \ ˈspärk-​ˌpləg How to pronounce spark plug (audio) \ transitive verb

Examples of spark plug in a Sentence

Recent Examples on the Web Rather, his push for a revival must be the spark plug to the team's overall success. Evan Petzold, Detroit Free Press, "Why Miguel Cabrera is boosted by playing first base, seeing fans in the stands," 1 Apr. 2021 Give your lawnmower a tuneup: change the oil, air filter and spark plug. Allen Foster,, "Lawn care: Best practices for spring and summer," 24 Mar. 2021 The dissimilar metals in the aluminum heads and the spark plug materials make removal of the plugs difficult — which means potentially costly. Motormouth Bob Weber, Star Tribune, "Motormouth: Changing spark plugs early isn't necessary," 18 Dec. 2020 This 51-piece kit comes with a wrench, ratchet, spark plug sockets, pliers, tire gauge, screwdriver and other items needed to fix a vehicle in an emergency situation. Hannah Drown, cleveland, "15 essential items for winter emergencies, snowstorms to keep in your car," 1 Dec. 2020 Where Anthony could fit with the Spurs, at least initially, is as a scoring spark plug off the bench. Jeff Mcdonald,, "Spurs draft profile: North Carolina’s Cole Anthony primed for NBA," 28 Oct. 2020 Lorenzo Cain, a spark plug in the leadoff spot, opted out of the season after one week. Tom Haudricourt, Milwaukee Journal Sentinel, "19 games in 17 days: That's the challenge underachieving Brewers face to make the playoffs," 10 Sep. 2020 There is another spark plug inside the cylinder that then ignites fuel in the normal way. Peter Valdes-dapena, CNN, "Maserati unveils its first supercar in 15 years," 9 Sep. 2020 If a conventional spark plug is like a lighter, Singleton’s plasma plug is more like a lightning bolt. Daniel Oberhaus, Wired, "Is Lightning-Fast Plasma the Key to a Cleaner Car Engine?," 9 Sep. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'spark plug.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of spark plug

1903, in the meaning defined at sense 1

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Time Traveler for spark plug

Time Traveler

The first known use of spark plug was in 1903

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Statistics for spark plug

Last Updated

9 Apr 2021

Cite this Entry

“Spark plug.” Dictionary, Merriam-Webster, Accessed 12 Apr. 2021.

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More Definitions for spark plug

spark plug


English Language Learners Definition of spark plug

: a part of an engine that produces a spark that makes the fuel burn

spark plug


Kids Definition of spark plug

: a device used in an engine to produce a spark that ignites a fuel mixture

More from Merriam-Webster on spark plug

Nglish: Translation of spark plug for Spanish Speakers Encyclopedia article about spark plug

Comments on spark plug

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