Jeff, I don't recall ever hearing that there is such a word. (But I am not an expert!) I was thinking of something like moniker. Then I went to thesaurus.com for "name" and got:
agname, agnomen, alias, appellation, autograph, autonym, brand, cognomen, compellation, denomination, designation, epithet, eponym, flag*, handle*, head, heading, label, matronymic, moniker, monogram, namesake, nickname, nom de guerre, nom de plume, nomen, patronymic, pen name, pet name, place name, prenomen, proper name, pseudonym, rubric, sign, signature, sobriquet, stage name, style, surname, tag, term, trade name
Maybe you could coin a term based on one of these. Geonym, maybe. crazy