back road UK /ˈbæk ˌɹəʊd/US /ˈbæk ˌɹoʊd/ noun1 •A secondary road, a little-used road, a road through rural areas sometimes used as an alternative to main roads.There was too much traffic on the highway, so I used a back road. It was very scenic, but I had to keep the speed down. formsback roads