When one has a loop of wire in a changing magnetic field (or a rotating wire loop in a constant magnetic field), Faraday's law says that an EMF -- i.e. a potential difference -- is created. But what does it mean for a loop of wire to have a potential difference? A loop of ideal wire should be an equipotential so unless we have to throw out the notion of ideal wire in this case, I don't see how a potential difference could but created in a single length of wire.
Note that I do understand that a current is created. And I can do the calculations in Faraday's law. I'm just looking for an explanation for what a potential difference in a single loop of wire is supposed to mean.