Lexington is a city in Henderson County, Tennessee, United States. Lexington is midway between Memphis and Nashville, lying 10 miles …Lexington is a city in Henderson County, Tennessee, United States. Lexington is midway between Memphis and Nashville, lying 10 miles south of Interstate 40, which connects the two cities. The population was 7,956 at the 2020 census. It is the county seat of Henderson County.