The term for “one who does not believe in God” is atheist.

Quick Scoop

An atheist is generally understood as someone who lacks belief in the existence of a god or gods.

Many modern definitions emphasize absence of belief rather than an active claim that “God does not exist.”

Related terms (mini-glossary)

  • Atheism : The state of having no belief in deities, or the view that there are no gods, depending on how strictly it is defined.
  • Agnostic : Someone who holds that we do not or cannot know whether any god exists.
  • Theist : Someone who believes that at least one god exists.

In casual conversation, if you’re talking about “one who does not believe in God,” the clearest single word is atheist.

TL;DR:
The standard word you’re looking for is atheist —a person who does not believe in God or gods.

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