glow plug


: a heating element in a diesel-engine cylinder to preheat the air and facilitate starting
also : a similar element for ignition in other internal combustion engines

Example Sentences

Recent Examples on the Web Thanks to active thermal management and ceramic glow plugs, an engine block heater is not needed until minus-22 degrees F, Chevy said. Jeff Yip, Houston Chronicle, 2 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'glow plug.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

circa 1941, in the meaning defined above

Time Traveler
The first known use of glow plug was circa 1941

Dictionary Entries Near glow plug

Cite this Entry

“Glow plug.” Dictionary, Merriam-Webster, Accessed 20 Mar. 2023.

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