Denizens

Denizens means residents.
"Disruption: A Blogger Mocks the Denizens of Silicon Valley"  by Nick Bilton, August 25, 2013 New York Times

A Demonym is the name for people who live in a country or locality, usually formed by adding suffixes "an", "er", "ite" and "ese" to the locale.  I have not seen any rule or pattern for these.



The most common suffix is just "n" because so many countries and locations end in the letter "a"
like:
Liberian
Indian
Albanian
Libyan
Bolivian
Jamaican
Tongan
Minnesotan


Add "an" (especially when the locale ends in a vowel)
Chicagoan
Chilean
European
Mexican
Haitian (pronunciation changes)

Also "ian" in the case of:
Parisian
Nigerian
Brazilian
(frequently , but not limited to, when the name ends in a consonant)

add a suffix "er" for many places like:
New Englander
Londoner
Berliner
New Yorker

add the suffix "ite" (usually cities)
for:
Muskovite (resident of Moscow)
Vancouverite
Denverite

add the suffix "ese" with:
Chinese
Congolese
Taiwanese

suffix "ish" for:
English
Danish
British
Irish

Add the suffix "i"
Bengali
Iraqi
Israeli

Sometimes the demonym derives from the language spoken there.
Angelinos (Los Angeles)
Breton (Brittany)
Boricua (Puerto Rico)
Québécois (Quebec)
Porteño (Buenos Aires)

And a lot of irregular endings like
Cypriot (Cyprus)
Spaniard (Spain)
French
Dutch
Hoosier (Indiana)

In the U.S. the demonym is often an adjective, such as "Alaskan salmon"
In Canada, usually not, such as "Canada Geese" or "Ontario Provincial Police"

The bottom line (here at the bottom) is that you go by what the denizens call themselves.