Englishunbeliever
noun
a Holy War against the unbelievers:
infidel, heretic, heathen, nonbeliever, atheist, nontheist, agnostic, pagan, nihilist, apostate, freethinker, dissenter, nonconformist;
disbeliever, skeptic, cynic, doubter, doubting Thomas, questioner, scoffer;
archaic paynim;
rare nullifidian.
▷antonyms believer.