adjective. ['ˌənbəˈliːvɪŋ'] rejecting any belief in gods.
adjective. ['ˌənbəˈliːvɪŋ'] denying or questioning the tenets of especially a religion.
adjective. ['ˌənbəˈliːvɪŋ'] holding that only material phenomena can be known and knowledge of spiritual matters or ultimate causes is impossible.