What would you call a gasoline-type engine, to distinguish it from a diesel, if it runs on a fuel other than gasoline?

This isn't an answer, but a further explanation of the question.

A diesel engine is so-called because it was invented by someone named Diesel. Diesel fuel is so-called, because it is meant to be burned in a diesel engine. A diesel engine can burn other things than diesel fuel, but it is still a diesel engine, because its name has nothing to do with what it burns.

The other common kind of internal-combustion engine is usually referred to as a gasoline engine, when there is a need to distinguish it from a diesel engine. In this case, however, the engine is being called after the fuel it usually burns, rather than the fuel being called after the kind of engine that burns it.

As with a diesel engine, a “gasoline” engine can run on fuels other than gasoline. For example, forklifts very often use this type of engine, but with propane rather than gasoline. (Propane burns more cleanly, making it safer to use as a fuel indoors where ventilation is limited, and forklifts are very often used indoors.)

A diesel engine, as I said before, is properly and logically called a diesel engine, regardless of what fuel it runs on.

What I was wondering is if there is a name for a “gasoline” engine (as opposed to a diesel) that is similarly proper and logical to call this engine by regardless of what fuel it might be using.

To be pedantic, I understand that Diesel cars do not have Diesel engines!! They are properly called Compression Ignition engines.

Diesel refers to the type of combustion used in the combustion cycle. a diesel will have a much higher compression ration because "diesel cycle" uses compression while other internal combustion engines use spark plugs to "fire" cylinders individually.
Yes some diesels use "glo-plugs" to initally heat the cylinders to fire the first few times, but a diesel runs off compression ignition, while Gas and some alt fuel vehicles do use a distributor system each cycle.
That being said, diesel type engines have been designed to run off anything from cooking oil to propane, and natural gas. (both of those are ost common in emergency generator applications where fuel storage is not safe, or difficult.

A gasoline engine is spark ignited. A diesel engine is pressure ignited. A gas engine has much lower compression than a diesel. If you increase the compression of a gas engine, you get detonation or the pressure igniting of the fuel.

Alternative-fuel engine springs to mind, but it´s a bit bulky. A Fossilfree engine is a possibility (like sugarfree gum), but a name like that would translate miserably into my native language. The Eco-engine, now that´s catchy (providing it´s ecological).