How do you call a male witch?

[Elemental]

Because "Oathbreaker" (probably more accurately "covenant breaker") refers to a very specific oath being broken. Which, as said, puts it perfectly in line with the term "Witch" when not referring to modern co-option or older etymology.

I didn't really want to go into that because of the prohibition on discussing religion, but you're right. As you are in regards to the connotations of witchcraft through the ages. The term witch itself though is neutral when divorced from its cultural and historical associations.