Katie from Mansfield, Texas, is curious about the term ruthless meaning merciless or having no remorse. In the 13th century, the word ruth meant the quality of being compassionate. Ruthless appeared in the language shortly thereafter, but the word ruth itself faded away. Linguists refer to such terms as unpaired words or missing opposites. Another example is disconsolate; although the word consolate was used centuries ago, it’s no longer used today. This is part of a complete episode.