"dweller" is usually combined with another word. city dweller apartment dweller cave dweller

Citizen is used when talking about something political. A resident is typically used (Not always) referring to a place where someone lives; for example: She resides in the greater metropolitan area.” Meaning that is were her house is. Inhabitant and dweller have very little difference. Inhabitant is usually used in geographic studies. Dweller is more archaic and typically seen in fantasy or older works of literature. 1. The government requires its citizens to vote. 2. Where did he take up residence? Is he still in this city. Is a resident here? 3. The inhabitants of the Appalachian foot hills speak a unique dialect of American English. 4. Moses dwelled there 40 years. The other dwellers barely noticed.

1- dweller is a kind of archive word and it rarely used. 2-. Citizen usually refers to a person who resides in a country and holds the passport of that country, regardless of the city. 3- Resident can be considered a little bit smaller than citizenship, it is not related to something from nationalities and governments, for example we can say, residents of the New York City, regardless of their citizenship. 4- Inhabitant is more related to races, tribes and small communities. For example inhabitants of a tribe in Africa.