Thomas Floyd Johnson (November 18, 1939 – December 31, 2024) was an American composer and music critic associated with minimalism. After a religious upbringing in Colorado, he studied at Yale with Allen Forte and in New York City with Morton Feldman. There he covered the work of several noted composers, bringing them to wider attention in The Village Voice. He was the first to apply the term minimal to music in his 1972 article "The Slow-Motion Minimal Approach".

He found inspiration in the ideas of ancient and early modern mathematicians and philosophers, and collaborated with contemporary mathematicians, while incorporating theatrical and visual elements in his work. Johnson often sought to engage audiences by explaining or narrating the processes of his music in or as part of the musical experience. He relocated to Paris in 1983, where he remarried in 1986 and lived until his death. His works include An Hour for Piano, The Four-Note Opera, Riemannoper, and the Bonhoeffer Oratorio.