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 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 Some monetary donations help cover oil for the weed trimmers and mowers, spark plugs for the machines and ant and weed killer. Kim Piña, Houston Chronicle, "Armed with mowers and goodwill, San Leon Yard Birds aid neighbors in need," 7 Oct. 2019 For the 27-year-old spark plug, he was said to be doing fine after getting the news. Chris Fedor, cleveland, "Cleveland Cavaliers devastated, surprised by abrupt Jordan Clarkson trade: ‘I fell to the ground, this one hurts’," 24 Dec. 2019 Minutes later, crew chief Tim Bourgoine was on a ladder, his arms and tools sunk inside the giant radial engine to fix a bad spark plug — a piffle as far as the average Flying Fortress bomber was concerned. Fredrick Kunkle, Washington Post, "Flight of restored B-17 bomber harks back to days when skies were not so blue," 12 Nov. 2019 Right in between them is the spark plug, which ignites the fuel. Avery Thompson, Popular Mechanics, "See-Through Engine Shows You the Marvel That Is Internal Combustion," 16 Jan. 2017 McClain was the spark plug for an offense that lost versatile athlete O’Shae Baker to ejection at the start of the second half for unsportsmanlike conduct. J.c. Carnahan,, "High School Football Rewind: Timmy McClain emerges for Seminole, Jeff Rolson wins Apopka debut," 31 Aug. 2019 After beginning the year in Triple-A New Orleans, the 29-year-old utility man has been a spark plug for the Marlins lineup, hitting .289/.346/.443 (110 wRC+), while providing tremendous defensive versatility. Wells Dusenbury,, "Jose Urena moving closer to return; Jon Berti making most of his opportunity with Marlins," 10 Aug. 2019 In a conventional four-stroke internal combustion gasoline engine, which works on the principle of suck-squeeze-bang-blow, the bang is created by a spark plug igniting the fuel-air mixture in the cylinder. Jonathan M. Gitlin, Ars Technica, "Swapping spark plugs for nanopulses could boost engine efficiency by 20%," 26 June 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

27 Jan 2020

Cite this Entry

“Spark plug.” The Dictionary, Merriam-Webster Inc., Accessed 28 January 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

Comments on spark plug

What made you want to look up spark plug? Please tell us where you read or heard it (including the quote, if possible).


showing steady, earnest care and effort

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