2. (Politics) A member of a secret association (esp. in Russia), which is devoted to the destruction of the present political, religious, and social institutions.
Frankly I don't know which of these is scarier. I see cases of usage 1 daily, and assuming the existence of usage 2 would parsimoniously explain a lot of otherwise nonsensical happenings in the world at large!
Nihilist's Creed: Reality cannot be measured if one must assume the reality of the measuring instrument.
Whew! Try selling that in the real world; another example of why ordinary people in the everyday world ask what their tax dollars are being wasted on in higher education these days?