> (i.e. the word pronounced my-newt)

"minute" comes from latin "pars minuta" and the "i" should be pronounced like in "minimum"

> By this logic, 0.016 (recurring) seconds should be a called a "third".

It should be "tertia". I found that in German and Polish it was used that way, but don't know about english:

https://de.wikipedia.org/wiki/Tertie_(Winkel)

https://pl.wikipedia.org/wiki/Tercja_k%C4%85towa

Should be the etymology of trice (but isn't). Odd omission from English.

Commodores had a 1/60 second "jiffy" for timing interrupts, that's all I could find.