Raven Ioor McDavid, Jr. was born on October 16, 1911 in Greenville, South Carolina to Raven Ioor and Marie Louise (Henderson) McDavid. In 1929 McDavid was a summer student at the Virginia Military Academy. He received a B.A. from Furman University in Greenville in 1931, and went on to Duke University for graduate school (M.A. 1933, Ph.D 1935).

From 1935 to 1938 McDavid was an English Instructor at the Citadel, a military academy in Charleston, South Carolina. From there he went on to teach at Michigan State University in East Lansing, Michigan. During World War II McDavid served as an advanced linguist in the language section of the United States Army. In 1952 McDavid joined the faculty of Western Reserve University in Ohio, where he remained until 1957 when he joined the University of Chicago faculty as an associate professor of English. In 1964 he was given the position of professor of English and Linguistics.

McDavid is perhaps best known for his work as the editor of the 1963 edition of H.L. Mencken's American Language. His work also includes The Structure of American English (1958), The Pronunciation of English in the Atlantic States (1961), Linguistic Atlas of the Middle and South Atlantic States (1979), and The Mirth of a Nation: America's Great Dialect Humor (with Walter Blair, 1983).

McDavid was a Rosenwald Fellow, a Fullbright Fellow, a senior fellow for the National Endowment for the Humanities, and a fellow of the American Anthropological Association. His professional memberships included the Modern Language Association, the Linguistic Society of America, the American Dialect Society, the Midwest Folklore Society, the Canadian Linguistic Association, and the National Association for the Advancement of Colored People (NAACP).

McDavid married Elizabeth Lee Harris on March 7, 1942. The couple, who divorced in 1945, had one daughter, Bettie McClain. On June 7, 1950 he married Virginia Ann Glenn. The couple had four children—Glenn Truxtun, Raven Ioor III, Thomas Ingelsby, and Ann Hamilton.