German engineer (born in France) who invented the diesel engine (1858-1913)
"The museum exhibit dedicated to Rudolf Diesel showcased models of his revolutionary internal combustion engines."
an internal-combustion engine that burns heavy oil
"The truck's diesel engine roared to life as we pulled onto the highway, chugging smoothly on its heavy oil fuel."
A fuel derived from petroleum (or other oils) but heavier than gasoline/petrol. Used to power diesel engines which burn this fuel using the heat produced when air is compressed.
"The truck needed a fresh tank of diesel because its engine relies on compressing air to ignite the heavy, petroleum-based fuel rather than a spark plug."
In plain English: A diesel is a type of fuel used to power big trucks, buses, and trains.
"The truck ran out of diesel and had to be towed."
Usage: As a noun, "diesel" refers to a heavy oil derived from petroleum used specifically to fuel diesel engines. You should use this term when talking about the fuel itself or vehicles powered by that engine type, rather than confusing it with gasoline.
To ignite a substance by using the heat generated by compression
"The engine's design allows air to be compressed so intensely that it spontaneously ignites the injected diesel fuel without any spark plugs."
In plain English: To diesel means to move very slowly and heavily, usually because of bad weather or traffic.
"The old truck diesel-ed right out of the garage and down the highway."
Usage: Do not use "diesel" as a verb to mean starting an engine; instead, say that you are "starting" or "cranking" a diesel engine. The term "diesel" remains strictly a noun referring to the fuel type or the inventor of the engine.
The word diesel comes from the name of its inventor, German engineer Rudolf Diesel. It entered English to refer to the heavy-duty engines he developed between 1892 and 1897.