Island is a home rule-class city in McLean County, Kentucky, in the United States. The population was 435 at the 2000 census. It is included in the Owensboro metropolitan area.It is named for Judge William Worthington's early 19th-century 8-square mile estate, known as The Island from the way high tide on the Green and other nearby rivers would maroon it from adjacent land. Between 1829 and 1860, the local post office operated as Worthington. The Owensboro and Nashville Railroad connected the area in 1872; the station and new post office were known as Island Station. Both were shortened to Island in 1882.