West Tennessee is one of the three Grand Divisions of the state of Tennessee. Of the three, it is the one that is most sharply defined geographically. Its boundaries are the Mississippi River on the west and the Tennessee River on the east. This region's boundaries have been expanded slightly to include all of Hardin County, which is bisected by the Tennessee River.Unlike the geographic divisions of most American states, the term West Tennessee has a legal as well as a socio-economic meaning.