Secularism

Secularism (noun) is the belief that life can be lived, and the universe understood, with little or no reliance on, or reference to, supernatural powers, such as gods. In a secular society, religion (or lack thereof) is a private matter, playing little role in discussions in common public forums.

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), and that religion is not as important in most people's lives as it once was.

See also agnosticism, atheism, rationalism and religion.

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secular (adjective).

In the meaning related to secularism above, it refers to things not religous or not related to the church.

The adjective is also used as a technical term in ephemerides (astronomy), and then refers to long-term perturbations in the motion of planets, as opposed to periodic perturbations. see e.g. month.