nonbeliever

noun

Etymology: Etymology tree English non- English believer English nonbeliever From non- + believer.

1. A person who does not believe, especially regarding religion.

   “The many nonbelievers he interviewed[…] were anything but antireligious, for example. […] At one point, he queries Jens, a 68-year-old nonbeliever, about the sources of Denmark’s very ethical culture.”