Someone who is very stupid or just ignorant, and can't comprehend the most basic things..

- 90% of the time this is all an act to piss off other people.

- Watch out for these people, they can be hard to spot sometimes, and at others, it's very easy.
Ex:

Joe: Oh yeah Avatar was a great movie!

*friend goes to see movie*

Billy: You son of a bitch! That was a chick flick designed to make women swoon. You're not so bright a bulb!
by KD42 February 28, 2011
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