Etymology corner -- a Shavuot special

British Chief Rabbi Sacks explains in a column in the London Times on the book of Ruth:

One Hebrew word epitomises the book: chessed, usually translated as “loving kindness”. It is what links the book’s main characters. In fact, it added a word to the English language. In Middle English, “ruth” meant kindness. Today only its negation remains: the word “ruthless”.

Interesting, although the Online Etymology Dictionary says it originates from 'Reuthe,' or 'Pity, Compassion,' which it traces back to the verb 'to rue.'