Thanatos is a Greek word meaning death. In Greek myth he is the personification of death. Mentioned often, he doesn’t visit mortals too regularly—otherwise there would be few alive to tell his tale.
Freud’s theories have been routinely challenged by depth psychologists, transpersonal psychologists and by spiritualists. At the other end of the spectrum, his ideas also have been questioned by clinical psychologists and psychiatrists.
But Freud still looms large in the humanities, mostly because he arguably was the first to try to systematically (some say scientifically) explore the hidden workings of the mind. So like him or lump him, he does deserve some respect.
¹ With help from – http://en.wikipedia.org/wiki/Thanatos