spark plug


: 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
: one that initiates or gives impetus to an undertaking
sparkplug transitive verb

Examples of spark plug in a Sentence

Recent Examples on the Web Trinity, the Dallas-area’s top rushing team in 6A, has its own offensive spark plug in star running back Josh Bell. Myah Taylor, Dallas News, 17 Sep. 2023 And there were two spark plugs per cylinder, mounted in the sides of the combustion chamber rather than using a single one in the center. Jonathan M. Gitlin, Ars Technica, 16 Oct. 2023 Outfielder David Peralta emerged as a spark plug in the dugout, leading to his train-horn hit celebration being adopted by the entire team. Jack Harris, Los Angeles Times, 18 Sep. 2023 Keep in Mind Many socket sets already contain a spark plug socket. Sarah Halverson, Better Homes & Gardens, 31 Aug. 2023 Nishida, the spunky, happy-go-lucky spark plug from Japan, bounced around leaping into teammates’ arms. Joe Freeman, oregonlive, 26 Jan. 2023 Which won’t be easy: James has been a breakout spark plug at this tournament, scoring a goal against Denmark in the group stage and then scoring a pair of goals and assisting on three others in England’s 6-1 rout of China in their final group-stage game. Sean Gregory, Time, 10 Aug. 2023 Senior center fielder Dax Raney was the Chargers’ spark plug on offense. Jason Frakes, The Courier-Journal, 27 May 2023 At 6-0, 215 pounds, Muncy is a spark plug on the Dodgers, but his inconsistency at the plate can be frustrating. Bernie Pleskoff, Forbes, 18 Apr. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'spark plug.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1903, in the meaning defined at sense 1

Time Traveler
The first known use of spark plug was in 1903

Dictionary Entries Near spark plug

Cite this Entry

“Spark plug.” Dictionary, Merriam-Webster, Accessed 5 Dec. 2023.

Kids Definition

spark plug

: a device used in an engine to produce a spark that ignites a fuel mixture
: one that begins something or drives something forward

More from Merriam-Webster on spark plug

Last Updated: - Updated example sentences
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