[mabub24]

Some of the words in music theory are just straight latin, or directly descendant from latin and old. A lot of people struggle with music theory until you "translate" it to using modern language (though you do lose some specificity in some cases). Like "ritardando", which is just "slow down", or accelerando, which is, you guessed it, "speed up".

You can also use arcane.

[yakubin]

Italian, not Latin. Italian is the language of music. Italy used to be the capital of European music. That's where it comes from. I also wouldn't classify it as mere "theory". It's basic notation that appears in notes. Calling it "theory" is like calling control flow constructs in Pascal (the language) "theory".

[noobly]

It's called music theory though? I agree it's a bad name, but that's what it's called..

[chuchana]

It is. This video argues it would be more accurate to call it the harmonic style of 18th century European musicians: https://www.youtube.com/watch?v=Kr3quGh7pJA

[namarie]

I think most of it is Italian instead of Latin, including your two examples.