A tightly curled tail is a feature of all spitz breeds - could be any of many breeds, do you know any more information (or if it is a crossword, how many letters?
Akita, Samoyed, Alaskan Malamute, Siberian Husky, Swedish Vallhund, German Spitz, Pommeranian, Japanese Spitz, Finnish Spitz, Norwegian Buhund, Swedish Lapphund, Finnish Lapphund, Japanese Shiba Inu, Canadian Eskimo Dog, Greenland Dog, Norwegian Elkhound, Basenji, I am sure there are others but these are the most common ones.