fundamentalist. Especially Christian and mainly "non-denominational" and "born again" -- that is, "taken Jesus into his/her heart as his/her 'personal savior'" (saved from?!??) -- Usually pejorative -- used as a negative (as entries at this site show). Often used to express frustration with people who are unwilling to actually debate, especially with regards to religion.
It looks like the fundies are back in the news; this time they're trying to bring prayer back in public schools.
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