- a state in the S central U.S. 69,919 sq. mi. (181,090 sq. km). Capital: Oklahoma City. Abbreviation: OK (for use with zip code), Okla.
- a state in the S central US: consists of plains in the west, rising to mountains in the southwest and east; important for oil. Capital: Oklahoma City. Pop: 3 511 532 (2003 est). Area: 181 185 sq km (69 956 sq miles)Abbreviation: Okla., (with zip code) OK
from Choctaw, literally “red people,” from okla “nation, people” + homma “red.” Coined by Choctaw scholar Allen Wright, later principal chief of the Choctaw Nation, and first used in the Choctaw-Chickasaw treaty of April 28, 1866. Organized as a U.S. territory 1889; admitted as a state 1907. Related: Oklahoman. State in the southwestern United States, bordered by Colorado and Kansas to the north, Missouri and Arkansas to the east, Texas to the south, and New Mexico to the west. Its capital and largest city is Oklahoma City.