For some reason, I got to thinking about the word "ruthless". I reasoned that "less" meant without, so the word meant "without ruth". Now my mother's name was Ruth, so I thought that was interesting. I went to my friend dictionary.com and looked up the word "ruth" (you can do the same here) and I found out that it means "pity or compassion". It's a good description of my mother who had both.
By the way, the slang definition of "ruth" is a women's bathroom, but I think without a women's bathroom is a pretty lame definition of "ruthless".