It's easy:
A = "No"
Theos = "God"
Hence, atheos = "no God"
Ergo, atheism = "belief in no god."
Despite all of this, fake atheists have been redefining the term "atheism" to mean a lack of belief in God.
More on the real definition of atheism:
Charles Darwin to John Fordyce: "I have never been an Atheist in the sense of denying the existence of God."
Webster's New World Dictionary of the American Language defines atheism as "the belief that there is no God, or denial that God or gods exist" (p. 87).
Collier's Encyclopedia: "Those who explicitly deny the existence of God, by virtue of some metaphysics whose key ideas positively excludes him" (Vol. I, P. 141).
Encyclopedia Britannica: "(1) as a denial that there is one supreme object of reverence; (2) as a denial that this object of reverence is also the all-inclusive reality; (3) as a denial that there is any one all-inclusive reality at all; (4) as a denial that the power which rules the world is worthy of our trust: (5) as a denial that this power is a Being with whom we may hold persnoal communion" (Vol. II p. 600).
Fun and Wagnall's New Encyclopedia: "atheism... denies the existence of deity" (Vol. I, p. 411).
Encyclopedia of Philosophy (Paul Edwards, ed.): "According to the most usual definition, an atheist is a person who maintains that there is no God, that is, that the sentence 'God exists' expresses a false proposition..." (Vol. I, p. 175).
