diesel engine

noun

: an internal combustion engine in which air is compressed to a temperature sufficiently high to ignite fuel injected into the cylinder where the combustion and expansion actuate a piston

Examples of diesel engine in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Hydrogen is injected into the cylinders at much lower pressure and temperature than in a diesel engine, and a spark causes ignition. — Jonathan M. Gitlin, ArsTechnica, 12 Aug. 2026 As a form of internal combustion engine (ICE), the new engine behaves much more like a diesel engine than earlier hydrogen engines. — Christopher McFadden, Interesting Engineering, 9 Aug. 2026 The technology wasn't ready; the compromises would be too great; diesel engines would always be the default. — Dea Jusufi, Forbes.com, 21 July 2026 While its inboard diesel engine gives it an operational cruising speed of 25 knots (29 mph, 46 km/h) and a range of 650 nautical miles, the craft can sprint up to a maximum speed of 55 knots (63 mph, 102 km/h). — David Szondy july 18, New Atlas, 19 July 2026 See All Example Sentences for diesel engine

Word History

First Known Use

1894, in the meaning defined above

Time Traveler
The first known use of diesel engine was in 1894

Browse Nearby Words

diesel-electric locomotive
diesel engine
diesel-engined
See all Nearby Words

Cite this Entry

“Diesel engine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diesel%20engine. Accessed 16 Aug. 2026.

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Kids Definition

diesel engine

noun
: an internal-combustion engine in which air is compressed to make enough heat to ignite the fuel in the cylinder

More from Merriam-Webster on diesel engine

Britannica.com: Encyclopedia article about diesel engine

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