Evangelical Atheist (noun)
also see: retard; hypocrite; asshole
An evangelical atheist is one who not only believes there is no god or other supreme being, but is obsessed with convincing everyone around them to become an atheist too, usually through hard-line intolerance (the kind they accuse other religions of). When cornered they usually try to put down their opponent's religion and bash them for 'blind faith', not realizing that their belief that there is no god is no more or less valid or provable than the other guy's belief that there is one.
Not to be confused with normal atheists/agnostics, who for the most part just dont talk about religion and accept the beliefs of those around them as their perogative. Evangelical atheists are particularly common on the Internet, as organized religion is generally accepted as part of 'the system' of global human society, and lately it's become cool on the Internet to hate 'the system'. Mostly teen angst, just instead of becoming whiny goth or emo, they take it a different direction.
Evangelical atheist: "Hi, I'm an atheist."
Other guy: "Cool, I'm Jewish."
Atheist: "YOU FOOL! YOU PRACTICE RELIGION LOL, YOU'RE A DUMBASS AND IM COOL BECAUSE IM AN ATHEIST. I SHALL NOW PROCEED TO EXPLAIN WHY BLIND FAITH IS DUMB, UNLESS ITS BLIND FAITH IN ATHEISM WHICH IS A COINCIDENTAL EXCEPTION"
Other guy: "Shut it bitch, you're a dumbass"
Atheist: "BUT IM AN ATHEIST, WHICH MEANS IM ALWAYS RIGHT. AND IM NOT AN INTOLERANT PRICK LIKE ALL MEMBERS OF RELIGION ARE, HURR HURR HURR."