You learn something new everyday. Today, I learned a new word – DEMONYM. Sounds ghoulish but is actually “a word that denotes the members of a people or the inhabitants of a place”, according to this definition.
The word comes from the Greek word for ‘populace’ (δῆμος demos) plus the suffix -onym and was popularized in 1997 by Merriam-Webster editor Paul Dickson in his book Labels for Locals.
The term is not widely employed or known outside geographical circles and does not appear in mainstream dictionaries. (Which explains, perhaps, why it popped out from the page at me.)