William Clarence Eckstine (July 8, 1914 – March 8, 1993) was an American jazz and pop singer and a bandleader during the swing era. He was noted for his rich, almost operatic bass-baritone voice. His recording of "I Apologize" (MGM, 1948) was given the Grammy Hall of Fame Award in 1999. The New York Times described him as an "influential band leader" whose "suave bass-baritone" and "full-throated, sugary approach to popular songs inspired singers like Earl Coleman, Johnny Hartman, Joe Williams, Arthur Prysock and Lou Rawls."