How do you define an atheist?

[wastepanel]

I've been in a discussion on another thread where we are attempting to define what an atheist is. Some of the points we have covered include those that do not know or have had no experience with religion. An example of this could be an alien on another planet that does not know of any religion. Further adding to the confusion is the discussion on dogs, cats, young babies, etc.(basically anything that cannot form a critical thought process).

My position is best summed up by saying (borrowed from said thread):

I consider the term "atheist" not as a grouping, but a word describing that person's thinking skills, reasoning, or belief cycle. It is an intangible item like happiness. It is not something to just place on an item to place it. It has a deep meaning and context to us. I apologize if I don't want to state that my desk and computer are atheists, because that is giving an inantimate object human emotions. I feel the same with animals or small babies. This is where alot of religions began before the introduction of science. They gave inanimate objects human emotions and/or abilities to explain their existance. I feel this is comparable.

Thanks for any coming posts/votes!