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
Electric cars also don't have radiators, fuel tanks, or exhaust systems that can cause problems, spark plugs that need to be replaced every 100,000 miles or so, oil that needs to be changed regularly, or mufflers that eventually wear out.
—
Keith Laing, USA Today, 17 June 2026
Turn your lawnmower upright and reattach the spark plug or battery.
—Brandee Gruener, Southern Living, 8 June 2026
Before sharpening, always disconnect the spark plug and safely remove the blade using gloves and a wood block.
—Helena Madden, Martha Stewart, 2 June 2026
Building off the trust shown by his coaches, Rosas has become Sandburg’s spark plug.
—Patrick Z. McGavin, Chicago Tribune, 28 May 2026
See All Example Sentences for spark plug
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Keith Laing, USA Today, 17 June 2026
Turn your lawnmower upright and reattach the spark plug or battery.
—Brandee Gruener, Southern Living, 8 June 2026
Before sharpening, always disconnect the spark plug and safely remove the blade using gloves and a wood block.
—Helena Madden, Martha Stewart, 2 June 2026
Building off the trust shown by his coaches, Rosas has become Sandburg’s spark plug.
—Patrick Z. McGavin, Chicago Tribune, 28 May 2026
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 19 Jun. 2026.
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