This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. One who does not believe or have faith, as in God or a philosophy.

n. a person who does not believe; especially regarding religion.

n. someone who refuses to believe (as in a divinity)

"What strikes me about the "nonbeliever" movement is the energy it expends trying to establish, and ultimately legitimize, a public footprint."

nonreligious person   

unbeliever   

irreligionist    materialist    atheist   

Beaver    Cheever    Seaver    achiever    beaver    believer    cleaver    dever    fever    griever   

blaggard    god-way    self-mockery    chuff    beguil    determinist    ejecta    exulting    disproof    thereout