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noun

diesel

DEE-zuhl
noun
1
A heavy fuel oil used in engines that ignite fuel through compression rather than a spark.
"The truck runs on diesel rather than regular petrol."
2
A diesel-powered engine or vehicle.
"They traded in the old diesel for a hybrid."
verb
1
For a petrol engine to keep running briefly after it’s switched off, due to residual heat igniting the fuel.
"The car dieseled for a second after I took the key out."

How to Use Diesel

Learner’s notes

In plain EnglishA fuel and engine type named after its inventor, ignited by compression rather than a spark plug.

Common pairings
diesel engine diesel fuel run on diesel

Word Forms

dieseled past tense, dieselled past tense, diesels singular

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The truck runs on _____ rather than regular petrol.

Etymology

Named after Rudolf Diesel, the German engineer who developed the compression-ignition engine in the 1890s.

Definitions: FreeDict original editorial