Actually synonyms could probably be "arrogant snobs" or "educated bigots" now that I think about it.
There are different levels of being a snob, especially in the liberal arts world. You have the light snob, who has selective tastes, but does not impose his preferences upon anyone and encourages people to think for themselves. These people can be highly beneficial because they encourage exploration and open-mindedness. Unfortunately, on the other side of the equation you've got (what I call) the "aggressive/arrogant snobs". These guys don't encourage open-mindedness; they KNOW they're right and they'll tell you that they're right, and will deem you an utterly worthless human being if you don't agree with them. They may be highly versed in a field like literature, but they use their powers to hurt and intimidate instead of to help and understand. They don't encourage looking outside the box; they encourage blind obedience to trends. "Mozart IS better than Salieri; and anyone who thinks otherwise is an uncultured peasant."
They're very closely related to bullies. In fact, they are bullies. But whereas we typically associate bullies with uneducated, uncultured, vulgar, insecure ruffians; these guys by contrast are informed, rarely vulgar, and highly educated. In fact, they can be very high up the social ladder (maybe even professors or government officials). However they contain underlying bigotry can easily move into areas of racism or sexism. And, like an evil Sherlock Holmes, they can usually convey this to you with (not so subtle) psychoanalysis.
"I can tell you don't like this kind of music => means you're an uneducated kid from a poor, uncultured family descending from more poor, low brow parasites of the earth. [If people like you were eliminated, the world would be a better place.]" [ ] = the last part is usually implied with a stupid smirk or a scowl.
or you can even have it from the opposite end
"I can tell you don't like popular music => you're a sad, lonely individual with a history of depression descending from a family with a history of social phobias and psychological problems, etc. Thus, you're passions tend to be wildly misplaced and the art world would be better without you."
They are also obsessively corrective in their area of expertise and will try to make you wish you were dead for getting one little fact wrong. It doesn't matter how benevolent your intentions are. You could be the nicest person in the world in a total nonprofit organization teaching an underpriviledged group of kids about the history of English literature free of charge. But if an aggressive snob finds you got one of your facts in your lectures even a little bit off, they will unleash holy hell against you. They will probably even go so far as to use your imperfections as evidence for as to why you and the kids you're teaching should avoid this field of education, and will try to convince you that you're doing widespread damage by trying to teach people in this field. Passion be damned. Aggressive snobs believe that only people like them are entitled to teach people about their field of specialty and everyone else who tries is a disillusioned parasite.
Aggressive snobs usually are more hateful of skeptics and indecisive people than others. This makes sense though. Since aggressive snobs are basically fanatics with a cultured attitude, they can't even begin to comprehend looking at a debate from the middle road. Such people who do assume the middle road are poisonous to their very nature, and feel to them like worse enemies than those who share an opposing view. You may ask: "What is truth?" Easy: "Truth" is whatever the aggressive snob says it is.
For me, aggressive snobs have always been more of a problem than the average bully. Bullies are generally direct with their attacks, but aggressive snobs are far more subtle and insidious. The casual way they pass judgment on you can really get under your skin and strike at the core of your integrity. You'll be thinking thoughts like "Well, that guy was a highly educated scholar...so he must know what was good for me, right?" Not exactly. For a person with self esteem problems, these attacks can cut real deep. They can paralyze you and send you into long periods of depression. "Maybe my whole life has been a waste of time..."
What to do if you encounter an aggressive snob? Just like bullies...remind yourself not to take ANYTHING they say personally. Their sociopathic, cynical attitude is not about you; it's about them. In reality have no authority to tell you how you should live your life, what you should be passionate about, or what your worth as a human being is; that's for you to figure out. Explore the world and discover your strengths/weaknesses for yourself.
Why not -5? Simple...encounters with them can provoke you to try to be better people if nothing else, to prove you're NOT like them.