Merriam-Webster Collegiate Dictionary - dakota

 I. noun  (plural ~s; also ~)  Etymology: ~ (Yankton-Yanktonai and Santee dialects) dakhota, perhaps literally, friendly, allied  Date: 1804  1. a member of an American Indian people of the northern Mississippi valley  2. the Siouan language of the ~ people  II. geographical name  1. — see James 1  2. territory (1861-89) NW United States divided 1889 into states of North ~ & South ~ (the ~s )  • ~n adjective or noun