/uj

I had to look it up.

Source confirming the main part of OP’s post: telex.hu/…/mi-a-fenet-jelent-az-hogy-abszolut-fil…

And then the term you’d want to look up for the claim about his last name is “endonym”, though you also don’t need to look further than the intro on this Wikipedia page en.wikipedia.org/wiki/Name_of_Hungary