The Dark(ish) Web

According to Andy Archibald, head of the UK cyber-crime-fighting unit, the Internet is rife with people building secret, closed spaces for nefarious means. And he is of course, correct.
“Dark Web”, not to be confused with “Deep Net”, “Dark Internet”, “The Undernet”. I guess the “cloud” concept has now stretched to the fluffy language used to describe all this stuff. What I get cross about is this lack of clear definition of two principals of Internet use:
So we’ve got a LOT of Internet that is hardly ever visited because Google etc. doesn’t give it high ranking (unintentional-censorship?) and on the other hand, networks like Tor, used by (depending on your political standpoint) villains, the oppressed or the paranoid.
Chances are, you are curious about both for different reasons. Anything that Google/Yahoo/Bing decides not to rank could be either an awesome demonstration of what one of my university lecturers would have defined as the pertinence. So you really are finding exactly what you need/want to find. But as the search engines are not inside your head, they can at best create a list based on what they think is relevant. So some readers will now be wondering if they are in fact getting the best search result they can and what goldmine pages are there hidden in the depths that they have never seen.
The other gloomy Internet concept is one where like-minded individuals, for whatever reason decide to build a protected network of resources to which only those “in the know” have access to. This is where the police and national governments are focussing attention. It is the battleground between encryption and cracking. It is full of egos, criminals, the politically oppressed, some truly awful individuals and voices that are prevented from speaking out in their own country. So pretty much a condensed variety of the human species.
Am I missing some standard definitions for these two very different situations? They are both things that could do with more attention but for vastly different reasons and it would be a shame to keep confusing them with vague jargon.