Learn English – n antonym of “ruthless”

While you can easily choose an antonym of ruthless here, it is worth noting that ruthful was actully a term used in the past:

• “Ruth” was a common word in Middle English, first appearing (as “reuthe”) around the 12th century, meaning “pity or compassion,” and in the 13th century we spoke of a person who was kind, charitable, and just generally felt your pain as being “ruthful.” (“Ruthful” has also been used at times to mean “inspiring compassion or pity,” i.e., pathetic, as well as “expressing grief” as in “ruthful weeping,” but these are secondary senses.)

• A person who lacked those qualities of kindness and charity, whose only concern was for personal gain and never shed a tear for the victims of his greed, has been, since the early 14th century, known as “ruthless,” literally lacking the quality of “ruth.”

• The “ruth” in “ruthful” and “ruthless” is a noun formed on the verb “to rue,” meaning “to feel sorrow or regret” (“And yet … no sooner was alone, Than she for loneliness her promise rued,” 1885), and which is still in wide use today (although perhaps not as much as it should be). Rue,” in turn, came from the Old English “hreowan,” which meant “to afflict with sorrow, pity or regret,” and which was rooted in old Germanic and possibly Norse words. “Rue” is perhaps most often found today in phrases such as “rue the day” (or hour, etc.), meaning, of course, to regret a decisive event which took place at that time (“France, thou shalt rue this houre within this houre,” Shakespeare, The Life and Death of King John, 1595).

• While “ruthless” is alive and well in popular usage today (and “ruthlessness” is even celebrated as a virtue on Wall Street), the sweet and gentle “ruthful” has almost entirely faded from our collective memory. The Oxford English Dictionary labels the word “archaic,” and its most recent citation for its use in print dates from the early 19th century. A search of Google News today for “ruthful” produces the epitaph “Your search – ruthful – did not match any documents,” which a quick perusal of the grim headlines confirms. It seems that this world could do with a “ruth transfusion” as soon as possible.

(www.word-detective.com)