[ithkuil]

Is it really ao blatant though? Is the word master ever been used to refer to a slave owner?

[ithkuil]

EDIT: ever been used to refer to anything other than a slave owner?

[ominous]

Yes. As a first example, I give you the default name for a git repository up to October 2020, on github. It wasn't used to mean "a slave owner".

And a second random example here: https://en.wikipedia.org/wiki/Mastering_(audio)