monarchy
n. C / Un. a system of government where a king or queen is the head of the country. In many modern versions, they have little power and mostly perform ceremonies.
n. a form of government in which supreme authority is vested in a single, usually hereditary, head of state. Often used to refer to the royal family or the institution itself.
The country changed from a monarchy to a republic.
In a constitutional monarchy, the king or queen acts as a symbolic figurehead while elected officials make the laws.
The transition from an absolute monarchy to a parliamentary system often involves a gradual shift of legislative power from the crown to an elected assembly.
From Old French monarchie, from Late Latin monarchia, from Ancient Greek μοναρχία (monarkhía), from μόνος (mónos, “only”) + ἀρχή (arkhḗ, “power, authority”). By surface analysis, mon- (“one, single”) + -archy (“rule, command”).
Uncountable when referring to the system of government; countable when referring to a specific country or state ruled by a monarch.