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 \ transitive verb

Examples of spark plug in a Sentence

Recent Examples on the Web

There also is a pretty simple explanation of how the spark plug ended up inside the formation. Erik Lacitis, The Seattle Times, "Proof of alien visitors? Artifact from an ancient civilization? The truth is out there — in Seattle," 1 Dec. 2018 But the Supreme Court hasn’t adjudicated a vertical merger since 1972 when a majority blocked Ford’s acquisition of a spark plug manufacturer. The Editorial Board, WSJ, "Trump’s Merger Appeal to Obama," 13 July 2018 Aside from a new gas tank, spark plugs, wires, fuel pump, fuel filter, air filter and fuel sending unit, the car is all-original and the replaced parts have been preserved and are included with the sale. Gary Gastelu, Fox News, "1987 Buick Grand National parked since 1991 up for auction with 74 miles on it," 25 Sep. 2018 Clarkson is an offensive spark plug, averaging 14.5 points and 1.3 three-pointers per game this season. Mike Barner,, "Fantasy Fallout of the Wild NBA Trade Deadline," 9 Feb. 2018 The senior guard hasn't been at 100% while dealing with a turf toe injury, but he's been a warrior and the spark plug during the Red Raiders' advancement. Scott Gleeson, USA TODAY, "NCAA tournament Sweet 16: Most important players for every March Madness team," 20 Mar. 2018 Shane Victorino, a Rule 5 draft pick who became the spark plug of a World Series champion, plans to retire next month after signing a one-day contract with the Phillies. Matt Breen,, "Shane Victorino to sign one-day contract, retire as a Phillie in August celebration," 3 July 2018 The Ecuadorian spark plug tallied the decisive score on a penalty kick in the 78th minute, inching the ball past United keeper David Ousted’s outstretched arms into the top-right pocket. Owen Pence,, "Revolution hold off D.C. United," 1 July 2018 Every team can use a player like Stephenson — a gritty, versatile defender who served as a spark plug off the bench during his second stint in Indiana. Sam Amick, USA TODAY, "LeBron James, Paul George and the top 40 NBA free agents of 2018," 28 June 2018

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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Last Updated

15 Dec 2018

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Time Traveler for spark plug

The first known use of spark plug was in 1903

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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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