The Chickasawhay River is a river, about 210 miles long, in southeastern Mississippi in the United States. It is a principal tributary of the Pascagoula River, which flows to the Gulf of Mexico. The Chickasawhay's tributaries also drain a portion of western Alabama. The name "Chickasawhay" comes from the Choctaw word chikashsha-ahi, literally "Chickasaw p…The Chickasawhay River is a river, about 210 miles long, in southeastern Mississippi in the United States. It is a principal tributary of the Pascagoula River, which flows to the Gulf of Mexico. The Chickasawhay's tributaries also drain a portion of western Alabama. The name "Chickasawhay" comes from the Choctaw word chikashsha-ahi, literally "Chickasaw potato".