to grieve for something done, to repent, is the Anglo-Saxon reow, contrition; German, reue. Rue (1 syl.).
called “herb of grace,” because it was employed for sprinkling holy water. Without doubt it was so used symbolically, because to rue means to be sorry, and penitence brings the water of grace with it. (Latin, ruta, from the Greek rhuo, so called because it sets persons free from disease and death.) (See Difference.) Ophelia says-
“There's rue for you, and here's some for me! we may call it `herb of
grace' o' Sundays.” —
A slip of land (free of all manorial charges and claims) encompassing or bounding manorial land. It certainly is not derived from the French rue, a street, nor is it a corruption of row. (See Rewe.)
“There is a whole world of curious history contained in the phrase Ragman's rewe, meaning a roll. In Piers Plowman's Vision, the pope's bull is called a rewe.” —Edinburgh Review, July, 1870.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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