Kitto's Popular Cyclopedia of Biblial Literature
A Saxon word signifying ruler or governor. In the Authorized translation of the Scriptures it is used without much discrimination for all the names applied to God, which cannot be helped, as our language does not afford the same number of distinguishing titles as the Hebrew. When, however, the word represents the dread name of Jehovah, it is printed in small capitals, Lord, and is by this contrivance made a distinguishing term. As the Hebrew name Jehovah is one never used with reference to any but the Almighty, it is to be regretted that the Septuagint, imitated by our own and other versions, has represented it by a word which is also used for the Hebrew 'Adonai,' which is applied not only to God, but, like our 'Lord,' to creatures also, as to angels (; ), to men in authority (; ), and to proprietors, owners, masters (). The leading idea of the Hebrew, the Greek, and the English words, is that of an owner or proprietor, whether God or man; and it occurs in the inferior application with great frequency in the New Testament. This application is either literal or complimentary; literal, when the party is really an owner or master, as in;;;;; , etc.; or when he is so as having absolute authority over another (; ), or as being a supreme lord or sovereign (); and complimentary, when used as a title of address, especially to superiors, like the English Master, Sir, as in;;; .
It cannot but be deemed desirable that, instead of the extensive use of the word Lord which we have described, discriminating terms should be adopted in translations. Apart from the Jewish superstitions which influenced the Seventy in their translation, there can be no good reason why the name Jehovah should not be retained wherever it occurs in the Hebrew. Then Lord might represent Adonai; or perhaps Sir, or Master, might be used when that word is applied to creatures; and God would very properly represent Elohim.
Kitto, John, ed. Entry for 'Lord'. "Kitto's Popular Cyclopedia of Biblial Literature". https://www.studylight.org/encyclopedias/eng/kbe/l/lord.html.