Origin and history of overlord

mid-13c., laverd, loverd, from Old English hlaford "master of a household, ruler, feudal lord, superior; husband," also "God," translating Latin dominus, Greek kyrios in the New Testament, Hebrew yahweh in the Old (though Old English dryhten was more frequent). Old English hlaford is a contraction of earlier hlafweard, literally "one who guards the loaves," from hlaf "bread, loaf" (see loaf (n.)) + weard "keeper, guardian" (from PIE root *wer- (3) "perceive, watch out for").

The modern monosyllabic form emerged 14c. Compare lady (etymologically "bread-kneader"), and Old English hlafæta "household servant," literally "loaf-eater." For elision of the -v-, compare hawk, head, lark, the prehistoric contraction in Harold, poetic e'en, e'er, o'er; Northern English and Scottish deil "devil," etc.

The meaning "an owner of land, houses, etc.," is from c. 1300; the sense in landlord. As the "usual polite or respectful form of address to a nobleman under the rank of a duke, and to a bishop" [OED, 1989] from 1540s. As an interjection from late 14c. Lords "peers of England," especially as represented in parliaments, is from mid-15c.

Lord's Prayer is from 1540s. Year of our Lord is from late 14c. (translating Latin anno domini) in reference to the incarnation of God in Christ. Lord knows (who, what, why, etc.), expressing a state of ignorance, is from 1711. Lord of the Flies (1907) translates Beelzebub (q.v.); William Golding's book was published in 1954. To drink like a lord is from 1620s.

word-forming element meaning variously "above; highest; across; higher in power or authority; too much; above normal; outer; beyond in time, too long," from Old English ofer (from PIE root *uper "over"). Over and its Germanic relations were widely used as prefixes, and sometimes could be used with negative force. This is rare in Modern English, but compare Gothic ufarmunnon "to forget," ufar-swaran "to swear falsely;" Old English ofercræft "fraud."

In some of its uses, moreover, over is a movable element, which can be prefixed at will to almost any verb or adjective of suitable sense, as freely as an adjective can be placed before a substantive or an adverb before an adjective. [OED]

Among the old words not now existing are Old English oferlufu (Middle English oferlufe), literally "over-love," hence "excessive or immoderate love." Over- in Middle English also could carry a sense of "too little, below normal," as in over-lyght "of too little weight" (c. 1400), overlitel "too small" (mid-14c.), oversmall (mid-13c.), overshort, etc.