For other forms of being secular, and perspective on the terminology underlying the word "secularism", see secularity.
in philosophy, the belief that one's own life can be best lived, and the universe best understood, with little or no reference to a god or gods or other supernatural concepts.
in society, any of a range of situations where a society less automatically assumes religious beliefs to be either widely shared or a basis for conflict in various forms, than in recent generations of the same society.
in government, a policy of avoiding entanglement between government and religion (ranging from reducing ties to a state church to promoting secularism in society).
Secularism can also mean the practice of working to promote any of those three forms of secularism.
In studies of religion, modern Western societies are generally recognized as secular:
There is near-complete freedom of religion (you can believe in any religion or none at all, with little legal or social sanction);
Religion does not dictate political decisions, though the moral views originating in religious traditions remain important in political debate in some countries, such as the United States; in some others, such as France (see Laïcité), religious references are considered out-of-place in mainstream politics.
Religion is not as important in most people's lives as it once was.
Proponents of secularism have long held a general rise of secularism in all the senses enumerated above, and corresponding general decline of religion in so called 'secularized' countries, to be the inevitable result of the Enlightenment project, as people turn towards science and rationalism and away from religion and superstition.