atheist
Americannoun
-
a person who does not believe in the existence of a supreme being or beings.
-
a person who believes that there is no supreme being or beings.
noun
adjective
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.
Related Words
See agnostic.
Other Word Forms
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.
Vocabulary lists containing atheist
The Catcher in the Rye
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
World Religions
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
The Stranger
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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.
Ayaan Hirsi Ali, having rejected the Islam of her youth and proclaimed her disbelief in God—she published “Infidel” in 2006—was for a time thought to be the next New Atheist.
From The Wall Street Journal • Oct. 17, 2025
Atheist Adventures offers non-believers in Los Angeles and beyond the opportunity to experience wonder and awe in the most inspiring places in the West.
From Los Angeles Times • Dec. 21, 2023
What's sad is that the New Atheist movement could have made a difference — a positive difference — in the world.
From Salon • Jun. 5, 2021
If the New Atheist movement of the early 2000s devoted itself to intellectual combat with the claims of Christianity, the more recent “exvangelical” movement elevates personal stories of people who have walked away.
From New York Times • Apr. 12, 2021
He avowed himself an Atheist when no one else did.
From Life and Character of Richard Carlile by Holyoake, George Jacob
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
