doubter
noun
[ ˈdaʊtə ]
• a person who questions or lacks faith in something; a sceptic.
• "he had proved all his doubters wrong"
Similar:
sceptic,
doubting Thomas,
non-believer,
unbeliever,
disbeliever,
cynic,
scoffer,
questioner,
challenger,
nihilist,
dissenter,
irreligionist,
atheist,
non-theist,
agnostic,
freethinker,
infidel,
pagan,
heathen,
paynim,
Pyrrhonist,
nullifidian,