Regime (noun)

1. A government, especially an authoritarian one.
2. A set of rules, principles, or conditions governing a particular activity or sphere of life.
3. A system or regimen of dieting or exercise.

Origin:

Late 18th century: from french régime "government, mode of rule", from latin regimen "rule, guidance", from regere "rule".

Examples:

1. The regime was overthrown by the people.
2. The regime's policies were criticized by the opposition.
3. The regime change brought a new government to power.
4. He is on a strict regime of diet and exercise.
5. The regime of the school is strict.