nihilist
noun
[ ˈnʌɪ(h)ɪlɪst ]
• a person who believes that life is meaningless and rejects all religious and moral principles.
• "it is impossible to argue against a nihilist"
Similar:
disbeliever,
unbeliever,
non-believer,
sceptic,
agnostic,
atheist,
non-theist,
negativist,
cynic,
pessimist,
anarchist,
