An “or” that means either this or that but not both.
This is an unusual type of or. Most ors are inclusive disjunctions, meaning “it could be this, that, or both: I’m honestly relaxed and don’t care as long as one of you shows up.”
If you have an inclusive or, as mostly you should, you don’t need an and/or. If (you think) you have an exclusive or, and you need an and, just use an inclusive or.
Plain English Anatomy™
Noun | Verb | Adjective | Adverb | Preposition | Conjunction | Latin | Germany | Flannel | Legal triplicate | Nominalisation | Murder your darlings