Try a dictionary for word meanings not an encyclopaedia<quoted text>
Atheism relies on belief or philosophy.
And it's not my definition, ColdPorcine.
"Atheism, from the Greek a-theos ("no-god"), is the philosophical position that God doesn't exist. It is distinguished from agnosticism, the argument that it is impossible to know whether God exists or not." -(Academic American Encyclopedia).
"Atheism is the belief that God doesn't exist." (The World Book Encyclopedia)
Atheism (Greek and Roman): "Atheism is a dogmatic creed, consisting in the denial of every kind of supernatural power. Atheism has not often been seriously maintained at any period of civilized thought" -(Encyclopedia of Religion and Ethics-Vol II).
Pedantic moron, search define atheism on google and you will see many, many definitions all essentially similar and all varying in their scope