Creatheists are atheists who argue like Creationists. They are usually ex-Creationists (but not always) who still haven't figured out that a bad argument is a bad argument, even if you take minimal time and even less brain-power to change the nouns in the premises.
Similarly, they don't understand that being an atheist doesn't inherently or necessarily make you any more logical, rational or informed than anyone else, as if belief in God is the ultimate litmus test for possessing sound rationale or objective thought. Creatheists tend to make very simple and/or flawed arguments against theism, akin to Creationists trying argue that Piltdown-man refutes all of evolutionary theory.
Typical Examples Edit
"God is supernatural, the supernatural doesn't exist, therefore God does not exist!"
"Philosophy doesn't prove anything." (Which is the Creatheist analogue of "evilution is just a theory".)