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Synonyms

atheist

American  
[ey-thee-ist] / ˈeɪ θi ɪst /

noun

atheists plural
  1. a person who does not believe in the existence of a supreme being or beings.

  2. a person who believes that there is no supreme being or beings.


atheist British  
/ ˈeɪθɪˌɪst /

noun

  1. a person who does not believe 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

adjective

  1. of or relating to atheists or atheism

"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

Usage

What does atheist mean? An atheist is a person who does not believe in the existence of a supreme being or deity. In other words, an atheist is a person who does not believe in the existence of God or of any gods. The belief or doctrine that denies the existence of gods or supreme beings is atheism. 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 atheist means something different from the word agnostic, which refers to a person who believes 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: Being an atheist doesn’t mean I think God is bad—it means that I think God doesn’t exist.

Synonym Usage

See agnostic.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of atheist

First recorded in 1565–75; from Greek áthe(os) “godless” + -ist; see a- 6 ( def. ), theo-

Explanation

An atheist believes there is no such thing as god, or any other deity. The root -theist means "belief in a god." The prefixes mono-, poly-, and a-, mean "one," "many," and "no," respectively. So a monotheist is someone who believes in a single god, a polytheist is someone who believes in many gods, and an atheist is someone who believes there is no god at all.

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Vocabulary lists containing atheist

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:

The country that houses the world’s second-largest Hindu temple is the U.S.—also home to the Christian street preacher, the Mormon missionary and the combative atheist.

From The Wall Street Journal May 12, 2026

Lou assumes her husband is an atheist and doesn’t understand when she discovers a Bible in the house.

From Los Angeles Times Nov. 18, 2025

He describes himself as an atheist and said it felt like "a bit of an imposition and probably a bit unfair and silly".

From BBC Nov. 17, 2025

China's officially atheist government has been wary of organized movements outside its control, and the country's Christians had been split among those attending unofficial "house" or "underground" churches and those visiting government-sanctioned places of worship.

From Barron's Nov. 3, 2025

While at the heart of Beethoven’s symphony lies a vision of a better civilisation led by a benign deity, Berlioz, a life-long atheist, attempts to evoke the Apocalypse and Final Judgement in sound.

From "The Story of Music" by Howard Goodall

Mr. Persico mentions that Martin Luther hated Jews and persecuted heretics, and he acknowledges that Locke excluded Catholics and atheists from toleration.

From The Wall Street Journal Oct. 24, 2025

You can see the evidence yourself: On social media, people are making teary videos professing to have rediscovered Jesus; in the comments, former atheists share stories of finding peace and purpose in prayer.

From Slate Oct. 1, 2025

Initially, it was billed as "1 Christian versus 20 atheists," but then one of the atheists outed Peterson, by simply asking Peterson a simple question: "Am I not talking to a Christian?"

From Salon Jun. 6, 2025

The religiously unaffiliated, including atheists and agnostics, made up 13% of global migrants who have left their country of birth.

From BBC Aug. 19, 2024

Since I learned the truth in Mecca, my dearest friends have come to include all kinds—some Christians, Jews, Buddhists, Hindus, agnostics, and even atheists!

From "The Autobiography of Malcolm X" by Alex Malcolm X;Hailey

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