seljak

1. peasant; farmer; villager
   Moj deda je bio seljak iz Šumadije. — My grandfather was a farmer from Šumadija.
   Seljaci prodaju sir i jaja na pijaci. — Farmers sell cheese and eggs at the market.
2. colloq. derog. yokel; hick; boor
   Ne budi seljak, pozdravi ljude! — Don't be such a boor, say hello to people!
   Neki seljak mi je ukrao parking mesto. — Some hick stole my parking spot.

In casual speech the word is often an insult, even when said about a city person.