Star is a city in northwestern Ada County, Idaho, United States. The population was 1,795 at the 2000 census. It was named in the 19th century by travelers on their way to Middleton and Boise who used the star on the school house to find east and west. The name stuck and it became Star, Idaho. Today it is a growing town west of Boise and its schools are shared with Middleton School District and Meridian School District.
Star is part of the Boise City–Nampa, Idaho Metropolitan Statistical Area.
Star is located at 43°41′39″N 116°29′25″W / 43.69417°N 116.49028°W / 43.69417; -116.49028 (43.694084, -116.490225). According to the United States Census Bureau, the city has a total area of 0.9 square miles (2.2 km²), all of it land.