A more thorough explanation:

Definition: Regency refers to the office or jurisdiction of a regent or a group of regents. It can also refer to a government or authority that is led by regents. The term is also used to describe the period during which a regent or group of regents governs.

1. When the king was too young to rule, a regency was established to govern the kingdom until he came of age.

2. The council of regents was responsible for making decisions on behalf of the queen during her illness.

3. The Regency era in England lasted from 1811 to 1820, when King George III was deemed unfit to rule and his son, the future King George IV, served as regent.

These examples illustrate the different ways in which the term "regency" can be used. In the first example, a regency is established to govern a kingdom when the rightful ruler is unable to do so. In the second example, a council of regents is responsible for making decisions on behalf of a ruler who is unable to govern due to illness. In the third example, the Regency era refers to a specific period in English history when a regent ruled in place of the king.