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Synonyms

atheism

American  
[ey-thee-iz-uhm] / ˈeɪ θiˌɪz əm /

noun

  1. disbelief or lack of belief in the existence of God or a supreme being or beings.

  2. the philosophical position stating that there is no supreme being or beings.


atheism British  
/ ˈeɪθɪˌɪzəm /

noun

  1. rejection of belief in God or gods

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

atheism Cultural  
  1. Denial that there is a God. (Compare agnosticism.)


Usage

What does atheism mean? Atheism is the belief that there is no supreme being or deity. In other words, atheism is the denial of the existence of God or of any gods. A person who holds such a belief can be called an atheist. The word atheist can also be used as an adjective to describe such beliefs or things involving such beliefs. The adjective atheistic can be used in the same way. The word atheism means something different from agnosticism, which is the belief that it is impossible to know whether or not a supreme being exists. When asked if God or gods exist, an atheist would answer “No,” while an agnostic would answer “It is impossible to know.”Example: Atheism isn’t the belief that God is bad—it’s the belief that God doesn’t exist.

Other Word Forms

Etymology

Origin of atheism

First recorded in 1580–90; from Greek áthe(os) “godless” + -ism; see a- 6 ( def. ), theo-

Explanation

Atheism is the lack of belief in the existence of a god or gods. Atheism isn't a religion — it's just the opposite. If you're fed up with religion or think that believing in God, heaven, and hell is silly, atheism just might be for you. An atheist doesn't believe in God or other supernatural beings. Some atheists state their belief more strongly, but it comes down to either "I don't believe in God" or "There is no God," which mean about the same thing. This is a stronger belief than agnosticism, which says we can't know if God exists.

Keep Reading on Vocabulary.com

Vocabulary lists containing atheism

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Beginning in the 1870s, atheism and indifference to religion became popular, especially among younger intellectuals.

From Salon Jun. 29, 2026

The first half of Communion, on Vance’s journey from evangelical Christianity to atheism to Catholicism, takes the reader through his disillusionment with the conservative evangelical churches of his youth.

From Slate Jun. 18, 2026

Few of the author’s converts came from committed atheism.

From The Wall Street Journal Apr. 3, 2026

Ishak Ibrahim, a researcher with the Egyptian Initiative for Personal Rights, said Egypt’s youth ministry announced plans in 2014 to combat atheism in collaboration with religious bodies.

From Seattle Times Oct. 4, 2023

I had to admit that I had never heard atheism of so militant a nature; but the Communist speaker seemed to be amusing and frightening the people more than he was convincing them.

From "Black Boy" by Richard Wright

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