William A. Lyon (January 21, 1903 – March 18, 1974) was an American film editor, from 1935 to 1971. He was born in Texas, and died in Los Angeles, California. Employed by Columbia Pictures for most of his career, he was nominated for the Academy Award for Film Editing six times, and won twice, for From Here to Eternity (1953) and Picnic (1955).