As a German surname, Luther is derived from a Germanic personal name compounded from the words liut, "salvation", and heri, "army".
As a rare English surname, it means lute player.
Eleutherius is a cognate of the Greek word eleutheros (ἐλεύθερος) which means "free".
As a personal name, Luther is a boy's name of German origin meaning "the salvation army".
It was once restricted to Evangelical Protestants honoring the ecclesiastical reformer and theologian Martin Luther, founder of the Protestant Church.