John Adair (January 9, 1757 – May 19, 1840) was an American pioneer, soldier, and politician. He was the eighth Governor of Kentucky and represented the state in both the U.S. House and Senate. A native of South Carolina, Adair enlisted in the state militia and served in the Revolutionary War, during which he was twice captured and held as a prisoner of war by the British. Following the War, he was elected as a delegate to South Carolina's convention to ratify the United States Constitution.