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 sparkplug (audio) \ transitive verb

Examples of spark plug in a Sentence

Recent Examples on the Web The maker of spectacular baskets in previous tournament games, the team’s senior spark plug did not take a shot. Mike Downey, Los Angeles Times, "Jim Harrick’s on-court adjustments served UCLA well in 1995 NCAA title win," 6 Apr. 2020 For the third time, a spark plug has been ejected from the engine. San Diego Union-Tribune, "2001 Expedition’s spark plugs are ready to blow!," 21 July 2019 Buying parts for your car in the 1970s typically meant asking a guy, slouched behind a grubby counter with a cigarette or toothpick in his teeth, to fetch a spark plug or wiper blade. James R. Hagerty, WSJ, "Co-Founder of AutoZone Enlivened a Dreary Branch of Retailing," 18 Mar. 2020 In gasoline engines, an electric spark plug ignites fuel in a cylinder to push a piston. Steven Ashley, Scientific American, "Can Diesel Finally Come Clean?," 19 Dec. 2019 Carefully inspecting/rerouting the spark plug wires may point out a problem there. Brad Bergholdt,, "Under the Hood: Stalling, hesitating has no clear cause in Forester," 15 Nov. 2019 Because of their unique situation, taking an offensive spark plug like Howard who can help them win now makes a lot of sense. Jeremy Cluff, azcentral, "NBA mock draft: Markus Howard leading nation in scoring, flying under the radar for draft," 20 Jan. 2020 The gun seen firing in the film is another mock-up which was not mounted on the helicopter and which consisted of metal tubing with spark plugs to ignite acetylene as it was blown through the barrels. Peter Opaskar, Ars Technica, "Forget Top Gun: Maverick—let’s settle Blue Thunder vs. Airwolf once and for all," 10 Jan. 2020 Bella Vogt is the team spark plug and has the capability to knock down big shots when needed. Mick Mccabe, Detroit Free Press, "McCabe: Detroit Edison, East Lansing top list of 20 high school girls basketball teams in state," 6 Dec. 2019

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

18 May 2020

Cite this Entry

“Spark plug.” Dictionary, Merriam-Webster, Accessed 28 May. 2020.

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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

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More from Merriam-Webster on spark plug

Rhyming Dictionary: Words that rhyme with spark plug

Spanish Central: Translation of spark plug

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

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