The term bass-baritone is sometimes used to mean a singer who has a range just slightly higher than that of a bass.
The word "baritone" is often applied to instruments to indicate their range in relation to other instruments of the same group. For instance the baritone saxophone. There is also a brass instrument called the baritone horn; it is unreleated to the French horn.
Some famous baritone singers include Thomas Allen, Pierre Bernac, Dietrich Fischer Dieskau, Robert Goulet, Thomas Hampson, John Shirley Quirk (perhaps bass-baritone), Gérard Souzay.