Of or pertaining to this present world, or to things not spiritual or holy; relating to temporal as distinguished from eternal interests; not immediately or primarily respecting the soul, but the body; worldly.
1) in relation to clergy, priests living in the world, not under a rule, who are bound by no vows and may possess property, working under the authority of a bishop: 2) more generally, refers to people who are not clergy, the laity
This term often refers to the things of this world as opposed to the things of God. Clergy living in the world and serving parishes have been known as ‘secular' since the 12th century. In Biblical times there was less of a division between the sacred and the secular. Today many Christians are arguing that the Incarnation (the belief that God became human in Jesus Christ) is a reason to challenge the separation of sacred and secular.
Confusingly in the context of Secularization, this word can mean both nonreligious and longterm. ST states that Western society is moving towards being secular (nonreligious) as a secular (longterm) trend.
In astronomy, secular mean that a phenomenon takes a tremendous amount of time to unfold, and occurs gradually. Secular change, for example, is a long-standing, continuous (and nonperiodic) change to a system.
Referring to long-term changes that take place slowly and imperceptibly. Commonly used to describe changes in elevation, tilt, and stress or strain rates that are related to long-term tectonic deformation. For example, a mountain that is growing is getting taller so slowly that we cannot see it happen, but if we were to measure the elevation one year and then the next, we could see that it has grown taller.