George R. Stewart, if he is remembered today at all, is noted as the writer of Earth Abides, a seminal work in the science fiction subgenre of the postapocalyptic novel. But to some language geeks he is hailed as an onomastician, a scholar of place names. Stewart, in the 1930s, is perhaps best known in the latter role for proposing a schema for how to identify someone according to their place of origin or residence.
Journalist and scholar H.L. Mencken was reportedly so impressed with the following distillation that he named them Stewart’s Laws of Municipal Onomastics:
1. Add -n to a place name ending in -a or -ia (Atlantan, Californian).
2. Add -an to a place name ending in -i or sounding like -e (Hawaiian, Baltimorean).
3. Add -ian to a place name ending in -on (Washingtonian).
4. Change -y to -i and add -an to a place name ending in -y (Schenectadian).
5. Add -an to a place name ending in -o (Ohioan).
6. Add -ite or -er to a place name ending in a consonant or a silent -e (New Englander, Seattleite).
7. Delete -s and add -tan to a place name ending in -polis (Annapolitan, for Annapolis).
That’s an impressive and helpful set of rules. Unfortunately, many people didn’t get the memo, so we find the rules widely broken. For example, someone from Florida is a Floridian, not a Floridan, and one writes of San Franciscans, not San Franciscoans. Parisians breaks the rules (it should be Parisite — ouch — or Pariser), as does Chinese (Stewart’s rule dictates Chinan).
Then there are classical affectations like Cantabrigian (Cambridge), Novocastrian (Newcastle, in Australia), and Oxonian (Oxford); more or less well-known foreign language alterations such as Flemish (Flanders), Madrileno (Madrid), and Muscovite (Moscow); and references — some famous, others obscure — based on state nicknames, think “Bay Stater” (Massachusetts), Hoosier (Indiana), and Nutmegger (Connecticut).
Thus, like many other attempts at codifying human behavior or custom, Stewart’s laws are breached as often as they are observed, but they’re still a useful guideline. Ultimately, though, let your fingers do the walking through a dictionary, geographical dictionary, atlas, or other resource.