BEAVERSVILLE: 1 mile northwest of Byars, on the site of old Camp Arbuckle. After the camp was abandoned by the military in 1851 the buildings were occupied by the Deleware Indians. It was named for Black Beaver, well known Indian scout.

BLANCHARD: Post office established 27 November 1906. Named for townsite developer, W. G. Blanchard.

BYARS: Post office established 9 April 1903. Named for Nathan H. Byars, local rancher

CAMP ARBUCKLE: 1 mile northwest of Byars. A military encampment established in May 1850, abandoned one year later after the selection of a permanent site farther south to be known as Fort Arbuckle. Named for Brigadier General Matthew Arbuckle.

CHISM: 6 miles northeast of Byars. A post office from 29 June 1900 to 15 September 1930. Named for William Chism, son of Jesse Chism, whose residence was nearby.

COLE: 7 miles southeast of Blanchard. A post office from 2 April 1912 to 31 August 1954. Named for Preslie B. Cole of McAlister, townsite owner.

COULSON: Near Rosedale. No longer in existence. A post office from 30 September 1902 to 31 December 1908. Named for Charles P. Coulson, first postmaster.

CRINER: 12 miles west of Purcell. A post office from 2 June 1910 to 15 October 1928. The name came from nearby Criner Creek, a branch of the Washita River, which had been named for George A. Criner, early-day rancher.

CURTY: Located in the southwestern part of the county. A post office from 5 April 1906 to 28 February 1914. No longer in existence.

DIBBLE: 15 miles west of Purcell. Post office established 22 May 1894. Named for James and John Dibble, local ranchers.

GOLDEN: 2 miles south of Byars. No longer in existence. A post office from 9 April 1896 to 21 April 1897. Named for W. T. Golden, local resident.

GOLDSBY: 6 miles north of Washington. Named for Frank W. Goldsby, prominent early-day resident.

JOHNSON: 2 miles northwest of Byars. Site of old Camp Arbuckle, often known as Beaversville. A post office from 5 October 1876 to 15 March 1910. No longer in existence, it was named for Montford Johnson, prominent Chickasaw rancher.

LEEPER: 16 miles northwest of Purcell. No longer in existence. A post office from 2 July 1888 to 21 July 1892. Named for William P. Leeper, rancher and prominent Chickasaw.

MCCLAIN COUNTY: Created at statehood, Named for Charles M. McClain, member of the Oklahoma Constitutional Convention.

MALVERN: 6 miles west of Purcell. No longer in existence. A post office from 3 November 1903 to 31 December 1905. Named for Malvern Hill, site of a Civil War battle in Virginia.

NEWCASTLE: 7 miles northwest of Norman. Post office established 26 March 1894. Named for Newcastle, Texas.

OKRA: Near Rosedale. No longer in existence. A post office from 26 July 1898 to 31 August 1908. Named for the garden vegetable.

PAYNE: 5 miles northeast of Lindsay. A post office from 15 December 1904 to 31 October 1922. Named for Jeff D. Payne, first postmaster.

PURCELL: County seat of McClain County. Record town for Recording district No. 18, Indian Territory. Post office established 21 April 1887. Named for E. B. Purcell of Manhatten, Kansas, Sante Fe Railway director.

ROSEDALE: 7 miles east of WAYNE. A post office from 25 August 1908 to 6 January 1961. Named for Rose Hopping, townsite allotee.

WASHINGTON: 10 miles northwest of Purcell. Post office established 10 May 1904. Named for George Washington, Caddo chief.

WAYNE: 6 miles south of Purcell. Post office established 11 December 1890. Took its name from Wayne, Pennsylvania.

WOMACK: 2 miles southeast of Blanchard. A post office from 6 August 1900 to 14 August 1909. Named for John C. Womack, proprietor of general store.