diesel engine

American  

noun

1. a compression-ignition engine in which a spray of fuel, introduced into air compressed to a temperature of approximately 1000° F (538° C), ignites at a virtually constant pressure.

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diesel engine British  

noun

1. a type of internal-combustion engine in which atomized fuel oil is sprayed into the cylinder and ignited by compression alone

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diesel engine Scientific  

/ dē′zəl /

1. An internal-combustion engine in which the fuel oil is ignited by the heat of air that has been highly compressed in the cylinder, rather than by a spark. Due to the need for the engine to withstand very high pressures, diesel engines are relatively heavy; however, they are relatively fuel-efficient, especially when running at low power.

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Etymology

Origin of diesel engine

First recorded in 1890–95

Example Sentences

As the skipper stopped the vessel, the roar of the diesel engine turned into a murmur, according to the Ukrainian military officers, who were in touch with the crew while they were at sea.

From The Wall Street Journal • Jun. 12, 2026

"I feel like I'm more of a diesel engine sometimes where I need to get going first, then at some point I'll start playing good tennis. I have to play a preparation tournament."

From Barron's • Jan. 3, 2026

"You couldn't tell the difference of a car with a petrol or diesel engine, I would like to say the same about an electric car," he said.

From BBC • Feb. 10, 2025

The main propulsion diesel engine shut down after the pumps lost electrical power.

From Seattle Times • May 14, 2024

The windows are down, and the diesel engine growls and rumbles when we stop at the red lights.

From "Free Lunch" by Rex Ogle

Related Words

• diesel