Also, I was apparently using my own personal definition of "engine" that was somewhat different than the other modern usage.
To me, a "motor" is something that translates energy into motion. An "engine" is something that translates energy into work. So a motor is a kind of engine, and uses of "engine" in knowledge work is an analogy.
English is just weird.
A motor produces locomotion. It makes other things move.
An engine produces power. Locomotion can be derived from power but isn't required to.
A train locomotive might be referred to as a "locomotive engine".
A car with an internal combustion engine moves from power generated by that engine. But a car with electric motors does not have an engine because power is not produced there. Power is produced elsewhere and then stored in the battery. Locomotion is produced by consuming the stored power.
Of course, that's just my interpretation of the two words without referring to a dictionary.
I am not at all sure why.
This is an enormously valuable concept: that plots require both participants and also people who do not just direct it or order it, or even just design it, hands off (often called "the architect of the plot"). They need people who are there from start to finish, like an author is; involved in every corner.
I almost always use the term motor for an electromechanical machine that turns electrical into mechanical power.
Like all words, there's ambiguity to it.
[0]: I've been working my way through this book: https://www.amazon.com/Design-Brushless-Permanent-Magnet-Mac...
Always thought calling car engine a motor is incorrect, shouldn’t be used interchangeably. In my experience machinery would be common name for both in engineering terms, not daily usage.
Motor converts equivalent forms of energy, or down, at very high efficiency. Electric to kinetic
And thus we get a common root for the words engine and genius. Fascinating.
Engines are chemically driven and use some flavor of combination to rotate a shaft.
Ehhh that's a stretch, unless we're talking Real Housewives type of "lay people".
As I understand it (within an engineering context), a "motor" converts electrical energy to mechanical energy, and an "engine" takes thermal/chemical/some other form of mechanical energy and outputs mechanical energy. But it's confusing because I've changed the "motor" in my old Honda when I was a teenager. So while I agree there is some nuance and blurry lines, not sure the two words are quite "interchangeable".
However, at some point since he retired, Estes transitioned to calling them Engine/Motors [2], and now, the primary labelling Estes uses calls them Engines, though Engine/Motor is still printed on the cardboard casing itself. [3]
Interestingly, the Spanish, French and German on the motors still use motor, as Motor, Moteur-Fusee and Raketenmotor, respectively.
Because of that upbringing, I have since treated the words to mean that a motor is something that provides force of motion (thrust or rotation) - it may or may not also be an engine, as in the rocketry examples. An engine is a contraption with moving/interacting parts that uses energy to accomplish some goal - that goal may (F-1, car engine) or may not (cotton gin, search engine) be the propulsion of the contraption itself and what it's attached to.
That said, as a child I made no such distinction, hence the frequent corrections. I am happy to recognize that in common vernacular they are usually synonymous, though it would still sound strange, I think, to call something a 'search motor' (edit: however, see comment by yau8edq12i !) or a 'graphics motor' just as it would be jarring to encounter 'servoengine'.
1: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi...
2: https://www.apogeerockets.com/bmz_cache/f/f8ecac9604d017a5c7...
3: https://estesrockets.com/products/b6-4-engines