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 To drive this car, the driver needed to explicitly control the air/fuel mixture and the point where the spark plug met the ignition. Nisha Talagala, Forbes, 21 June 2021 Try calling her Softball America freshman of the year, UCLA’s power-hitting left-hander or a do-it-all defensive spark plug. Houston Mitchell Assistant Sports Editor, Los Angeles Times, 29 Apr. 2021 Nobody at the spark plug factory can get a raise if sales are declining. Frank Lavin, Forbes, 10 Mar. 2021 Rather, his push for a revival must be the spark plug to the team's overall success. Evan Petzold, Detroit Free Press, 1 Apr. 2021 Give your lawnmower a tuneup: change the oil, air filter and spark plug. Allen Foster,, 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, 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, 1 Dec. 2020 Where Anthony could fit with the Spurs, at least initially, is as a scoring spark plug off the bench. Jeff Mcdonald,, 28 Oct. 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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Dictionary Entries Near spark plug

spark photography

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Last Updated

2 Jul 2021

Cite this Entry

“Spark plug.” Dictionary, Merriam-Webster, Accessed 31 Jul. 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


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