Reign

v. possess sovereign power, rule, control, govern; predominate, prevail, be widespread

n. rule, government; period of rule, period of time that a particular government is in control

A reign is a period of time a person serves as a monarch or pope. No time limit exists on reigns, nor is there a term of office. Thus a reign usually lasts for the remainder of the monarch's life, unless the monarchy itself is abolished or the monarch abdicates.The term of a reign can be indicated with the abbreviation "r." after a sovereign's name, such as the following:George VI, King of the Dominion of Canada (r. 1936–1952)
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Noun
1. a period during which something or somebody is dominant or powerful; "he was helpless under the reign of his egotism"
(hypernym) time period, period of time, period
(hyponym) reign of terror
(derivation) predominate, dominate, rule, prevail
2. the period during which a monarch is sovereign; "during the reign of Henry VIII"
(hypernym) historic period, age
3. royal authority; the dominion of a monarch
(synonym) sovereignty
(hypernym) dominion, rule
(hyponym) scepter, sceptre
Verb
1. have sovereign power; "Henry VIII reigned for a long time"
(hypernym) govern, rule
(derivation) sovereignty
2. be larger in number, quantity, power, status or importance; "Money reigns supreme here"; "Hispanics predominate in this neighborhood"
(synonym) predominate, dominate, rule, prevail
(hyponym) override

(n.)
To possess or exercise sovereign power or authority; to exercise government, as a king or emperor;; to hold supreme power; to rule.
  

(n.)
To have superior or uncontrolled dominion; to rule.
  

(n.)
The time during which a king, queen, or emperor possesses the supreme authority; as, it happened in the reign of Elizabeth.
  

(n.)
The territory or sphere which is reigned over; kingdom; empire; realm; dominion.
  

(n.)
Royal authority; supreme power; sovereignty; rule; dominion.
  

(n.)
Hence, to be predominant; to prevail.
  

The duration of rule by a king , prince or noble , taking the form ‘...In the fourth year of the reign of king Stephan....’ In an SCA context, the reign of a king lasts for approximately six months, except in the West kingdom, where reigns are four months in length.