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

From spark plugs to engines to assembly, the GM locations dumped 10 million gallons of waste into the river every day, according to the Interior report. Dustin Renwick, National Geographic, "Five years on, the Flint water crisis is nowhere near over," 25 Apr. 2019 Other automotive products that are part of the sale include motor oil, spark plugs, cleaning products, car audio components, and garage accessories. Drew Dorian, Car and Driver, "Walmart Offering Tires at Huge Discounts for Memorial Day," 20 May 2019 This is his battlefield against cogwheels, fan belts, carburetors and radiators, spark plugs, and batteries. Amos Oz, Harper's magazine, "Setting the World to Rights," 10 Apr. 2019 In most cases, the metal is melted using an electrical arc, like in spark plugs. Nicholas Wicks, Popular Mechanics, "Tool Test: What's the Best Entry-Level Welder?," 23 Dec. 2017 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

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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Statistics for spark plug

Last Updated

14 Jul 2019

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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

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).


to form ideas or theories about something

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