paganism, heathendom
The rejection of, or opposition to, religious beliefs, (inherent or objective) moral principles, legal rules, etc., often due to the view that life is meaningless (sense 1).
A doctrine grounded on the negation of one or more meaningful aspects of life; in particular, the view that nothing in the world actually exists.
The rejection of non-proven or non-rationalized assertions in the social and political spheres of society.
A delusion that oneself or the world, or parts thereof, have ceased to exist.
Something that is regarded as meaningless.
The view that all endeavours are devoid of objective meaning.