Words mean what they mean, of course, but the images they call to mind subtly shape our understanding of their official meaning. Latin dominus is the master of a household, the paterfamilias. The root of Greek kurios means "strong," and implies the ability to break down resistance, not the right to obedience. It might best be translated, "Boss." Hebrew Adonai is an exclusively divine title, though its cognates in other languages can mean a secular ruler. Aramaic Mari is preserved in the ancient town name and in other contexts, such as the ruler of a city. Marana tha! means, "Our lord, come!" and shows how Jews using Aramaic employed the word as a direct translation of Adonai.
Unfortunately, 21st Century Americans are most likely to meet the term "lord" only in disambiguated religious contexts or in its debased meaning of a British aristocrat. But in its fulness, the word we are using is part of a family of meanings which shade into each other: God of Israel, Master, Giver of Daily Bread, Head of the Household, Ruler of the City of God, Commander, Healer of my Soul.
