Most countries of the Middle East and North Africa maintain a dual system of
courts and religious courts, in which the religious courts mainly regulate marriage and inheritance.
Apostasy in Islam - Wikipedia
Much more rarely,
not a member of the clergy
not belonging to a specific religious order
can reference long time spans in various senses such as:
a one-time rather than a cyclical event — such as
a secular decrease in real estate prices
a secular rather than a periodic planetary perturbation
a once-in-an-age or once per century event — such as
The Secular Games of Rome
refers to a state where a radioactive isotope decays at the same rate at which it is produced.
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