Product names which are derived after an inventor's name will often remain capitalized, though not always (e.g. the petroleum distillate used to power trucks and locomotives is called "diesel" rather than "Diesel" even though it's named after the inventor of the four-stroke compression-ignition engine for which that fuel was formulated).
I suppose a more realistic example is the development of powered pumps, locomotives etc. Newcomen's atmospheric engine did a vital job, but was bettered by Watt's improvements. Trevithick's locomotive of 1804 hauled a load, but modern diesel engines work far more efficiently and reliably. // I'm not sure this is really an English language question.
Even with uncountable nouns, for specific instances/types, we have nouns preceded by indefinite articles as in the following examples. It is cold outside! I could do with a hot tea! The old diesel
What’s the difference between particulate and particle? Should it be diesel particulates or diesel particles, and why? Could you provide three or more examples where it should use particulate rat...
Gas is flammable, diesel vapour combustible. In England I was always taught that the difference between flammable and inflammable was that inflammable required a flame to permit burning.
Animated by Studio Ghibli, the film stars Minami Takayama, Rei Sakuma, Kappei Yamaguchi, and Keiko Toda. The story follows Kiki (Takayama), a young witch who moves to the port city of Koriko with her cat Jiji (Sakuma) and starts a flying courier service.
Kiki is a slang term used for an informal gathering among close friends, typically involving laughter and gossip. More generally, it means “a gossipy conversation” or “to chat,” especially on a colorful topic. It is especially used in and associated with LGBTQ+ and Black communities.