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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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
Acuña has been a spark plug of sorts for the lineup but was left on the bench twice in Arizona earlier in the week.
—Abbey Mastracco, New York Daily News, 9 May 2025
The 5-foot-10 spark plug has superb quickness, an asset in the slot, but terrible long speed judging by his 40-yard dash time pre-draft (4.71).
—Andrew Callahan, Boston Herald, 2 June 2025
See All Example Sentences for spark plug
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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
Acuña has been a spark plug of sorts for the lineup but was left on the bench twice in Arizona earlier in the week.
—Abbey Mastracco, New York Daily News, 9 May 2025
The 5-foot-10 spark plug has superb quickness, an asset in the slot, but terrible long speed judging by his 40-yard dash time pre-draft (4.71).
—Andrew Callahan, Boston Herald, 2 June 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 22 Jul. 2025.
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