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
Recent Examples on the Web
Anthony is more of a spark plug than a true lead guard.
—
Brian Sampson, Forbes.com, 31 July 2025
There were problems during the record run, a fuel leak to a fouled spark plug.
—James Raia, Mercury News, 27 July 2025
Image The metals also go into the chemicals for manufacturing jet engines, lasers, car headlights and certain spark plugs.
—Keith Bradsher, New York Times, 13 Apr. 2025
Replace the spark plug and the air filter, and then change the mower engine's oil.
—Michelle Ullman, Better Homes & Gardens, 26 Sep. 2024
See All Example Sentences for spark plug
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Brian Sampson, Forbes.com, 31 July 2025
There were problems during the record run, a fuel leak to a fouled spark plug.
—James Raia, Mercury News, 27 July 2025
Image The metals also go into the chemicals for manufacturing jet engines, lasers, car headlights and certain spark plugs.
—Keith Bradsher, New York Times, 13 Apr. 2025
Replace the spark plug and the air filter, and then change the mower engine's oil.
—Michelle Ullman, Better Homes & Gardens, 26 Sep. 2024
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 3 Aug. 2025.
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