spark plug
noun
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
Examples of spark plug in a Sentence
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Their first couple of men off the bench, former Sixth Man of the Year Naz Reid and Donte DiVincenzo, are spark plugs.
—
Fred Katz, New York Times, 16 Oct. 2025
Tampa Bay hopes to have back WR Mike Evans for Monday, but could be missing spark plug rookie WR Emeka Egbuka as well as WR Chris Godwin and RB Bucky Irving again.
—Miami Herald, 16 Oct. 2025
Unlike gasoline internal combustion engines that use spark plugs to ignite the compressed air and fuel mixture in the combustion chamber of each cylinder, diesel engines operate without an external spark.
—New Atlas, 6 Oct. 2025
Miles McBride is a spark plug at the point guard spot, and Landry Shamet is a deadly 3-point shooter.
—Robert Marvi, MSNBC Newsweek, 6 Oct. 2025
See All Example Sentences for spark plug
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Fred Katz, New York Times, 16 Oct. 2025
Tampa Bay hopes to have back WR Mike Evans for Monday, but could be missing spark plug rookie WR Emeka Egbuka as well as WR Chris Godwin and RB Bucky Irving again.
—Miami Herald, 16 Oct. 2025
Unlike gasoline internal combustion engines that use spark plugs to ignite the compressed air and fuel mixture in the combustion chamber of each cylinder, diesel engines operate without an external spark.
—New Atlas, 6 Oct. 2025
Miles McBride is a spark plug at the point guard spot, and Landry Shamet is a deadly 3-point shooter.
—Robert Marvi, MSNBC Newsweek, 6 Oct. 2025
See All Example Sentences for spark plug
Cite this Entry
“Spark plug.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spark%20plug. Accessed 20 Oct. 2025.
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