“Their first meeting around Johnson's dinner table ended in a quarrel since Wollstonecraft disagreed with Godwin's sweeping atheism.”
“Yet this could represent the Ghost's embodiment of the disciples' moment of doubt and fear, rather than the atheism of modern generations.”
“The novel focuses on the conflicts between atheism and theism, Leninism and Marxism.”
atheist
A person who does not believe in deities.
(narrowly) A person who believes that no deities exist (especially, one who has no other religious belief).
(broadly) A person who rejects belief that any deities exist (whether or not that person believes that deities do not exist).
(loosely) A person who has no belief in any deities, such as a person who has no concept of deities.
(uncommon) A person who does not believe in a particular deity (or any deity in a particular pantheon), notwithstanding that they may believe in another deity.