Synonyms for "irreligion": agnosticism, heresy, nonbelief, infidelity, profanity, paganism, secularism, nihilism, irreverence, libertinism, disbelief, free thought, desecration, rationalism, impiety, humanism, blasphemy, materialism, skepticism, hedonism, sacrilege, indifference, unbelief, agnosis, apostasy, unfaith, atheism.