"The noble duke my master,
My worthy arch and patron comes to-night."
(Lear, ii. 1.)
Occurring chiefly in such phrases as arch enemy, arch heretic, arch hypocrite, arch rogue, it acquired a depreciatory sense, which has now become so weakened that archness is not altogether an unpleasing attribute. We may compare the cognate German prefix Erz. Ludwig has, as successive entries, Ertz-dieb, "an arch-thief, an arrant thief," and Ertz-engel, "an arch-angel." The meaning of arrant is almost entirely due to association with "thief." It means lit. wandering, vagabond, so that the arrant thief is nearly related to the knight errant, and to the Justices in eyre, Old Fr. eire, Lat. iter, a way, journey. Fr. errer, to wander, stray, is compounded of Vulgar Lat. iterare, to journey, and Lat. errare, to stray, and it would be difficult to calculate how much of each enters into the composition of le Juif errant.
As I have suggested above, association accounts to some extent for changes of meaning, but the process is in reality more complex, and usually a number of factors are working together or in opposition to each other. A low word may gradually acquire right of citizenship. "That article blackguardly called pluck" (Scott) is now much respected. It is the same word as pluck, the heart, liver, and lungs of an animal—
"During the Crimean war, plucky, signifying courageous, seemed likely to become a favourite term in Mayfair, even among the ladies."
(Hotten's Slang Dictionary, 1864.)
Having become respectable, it is now replaced in sporting circles by the more emphatic guts, which reproduces the original metaphor. A word may die out in its general sense, surviving only in some special meaning. Thus the poetic sward, scarcely used except with "green," meant originally the skin or crust of anything. It is cognate with Ger. Schwarte, "the sward, or rind, of a thing" (Ludwig), which now means especially bacon-rind. Related words may meet with very different fates in kindred languages. Eng. knight is cognate with Ger. Knecht, servant, which had, in Mid. High German, a wide range of meanings, including "warrior, hero." There is no more complimentary epithet than knightly, while Ger. knechtisch means servile. The degeneration of words like boor,[60] churl, farmer, is a familiar phenomenon (cf. villain, p. [150]). The same thing has happened to blackguard, the modern meaning of which bears hardly on a humble but useful class. The name black guard was given collectively to the kitchen detachment of a great man's retinue. The scavenger has also come down in the world, rather an unusual phenomenon in the case of official titles. The medieval scavager[61] was an important official who seems to have been originally a kind of inspector of customs. He was called in Anglo-French scawageour, from the noun scawage, showing. The Old French dialect verb escauwer is of Germanic origin and cognate with Eng. show and Ger. schauen, to look. The cheater, now usually cheat, probably deserved his fate. The escheators looked after escheats, i.e., estates or property that lapsed and were forfeited. The origin of the word is Old Fr. escheoir (échoir), to fall due, Vulgar Lat. ex *cadēre for cadĕre. Their reputation was unsavoury, and cheat has already its present meaning in Shakespeare. He also plays on the double meaning—
"I will be cheater to them both, and they shall be exchequers to me."
(Merry Wives, i. 3.)