spark plug

noun

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

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 McCulloch, once a teacher in Tennessee, had long been the spark plug of her family, prone to dancing in supermarket aisles and striking up conversations with complete strangers. Adam Geller, BostonGlobe.com, 13 May 2022 McCulloch, once a teacher in Tennessee, had long been the spark plug of her family, prone to dancing in supermarket aisles and striking up conversations with complete strangers. Adam Geller, Chron, 14 Apr. 2022 Whitmore became a spark plug for the USA offense, with explosive dunks helping shift the momentum. oregonlive, 8 Apr. 2022 McCulloch, once a teacher in Tennessee, had long been the spark plug of her family, prone to dancing in supermarket aisles and striking up conversations with complete strangers. Adam Geller, Chron, 14 Apr. 2022 McCulloch, once a teacher in Tennessee, had long been the spark plug of her family, prone to dancing in supermarket aisles and striking up conversations with complete strangers. Adam Geller, Hartford Courant, 13 Apr. 2022 Anyone who has fussed with the model knows that to replace the rear-most spark plug on the driver’s side of a US-spec car, the unfortunate mechanic must gain access through a plate on the interior firewall, or simply pull the engine. Robert Ross, Robb Report, 18 Apr. 2022 Johnson was a huge spark plug for North Carolina in the game, scoring 11 points in 18 minutes off the bench. Jeremy Cluff, The Arizona Republic, 5 Apr. 2022 Some online prices for the same spark plug are almost half the cost. Bob Weber, chicagotribune.com, 21 Oct. 2021 See More

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.

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

spark plug

sparkproof

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Statistics for spark plug

Last Updated

15 May 2022

Cite this Entry

“Spark plug.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spark%20plug. Accessed 16 May. 2022.

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More Definitions for spark plug

spark plug

noun

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

Britannica.com: Encyclopedia article about spark plug

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