DQN (dokyun)

This is a net-slang so usually people use it on the internet only.

In the TV show "Mokugeki Dokyun", people who got interviewed seem to lack common sense.

And they look like a person with little education.

So someone who has no common sense on the internet called DQN.

And also people call DQN校 (DQN school) for schools with low standardized scores.