ruler
Americannoun
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rulers
plural
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a person who rules or governs; sovereign.
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Also a strip of wood, metal, or other material having a straight edge and usually marked off in inches or centimeters, used for drawing lines, measuring, etc.
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a person or thing that rules paper, wood, etc.
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Astrology. the planet primarily associated with any sign of the zodiac or any house of the horoscope.
The ruler of Aries is Mars. The ruler of Taurus is Venus.
noun
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a person who rules or commands
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Also called: rule. a strip of wood, metal, or other material, having straight edges graduated usually in millimetres or inches, used for measuring and drawing straight lines
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of ruler
Middle English word dating back to 1325–75; see origin at rule, -er 1
Explanation
The leader of a country is a ruler. If you're a queen, a sultan, or a czar, you're a ruler. Besides "person who rules or governs," you can define ruler as a measuring device that's marked with inches or centimeters. You can measure the diameter of a circle with a ruler, and you can also draw a perfectly straight line using its edge. Both meanings stem from the verb rule, "to exercise power" or "to control," which came to also mean "mark with lines" in the 1590s.
Vocabulary lists containing ruler
Measurement and Data, List 2
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"Culture Clash"
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Measurement and Data
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Piqued, Burkina's military ruler Ibrahim Traore complained the country's football was "in a sorry state" and threatened "significant decisions" to "remedy it".
From Barron's ● Oct. 8, 2026
Both are state-backed and led by the ruler of Dubai’s uncle.
From The Wall Street Journal ● Oct. 7, 2026
Dolly Parton — the “queen of country,” benevolent ruler of Dollywood and America’s true sweetheart — died at age 80 last month.
From Los Angeles Times ● Sep. 15, 2026
A traditional Ugandan ruler named as the world's youngest monarch has died aged 34, his prime minster announced.
From BBC ● Aug. 28, 2026
I was not just the ruler of one planet.
From "Klawde: Evil Alien Warlord Cat" by Johnny Marciano and Emily Chenoweth
The ambassador, who was appointed by Suu Kyi's government, broke with his country's rulers weeks after their putsch.
From Barron's ● Sep. 13, 2026
Their monarchs are recognised as cultural leaders rather than political rulers.
From BBC ● Sep. 10, 2026
Alexander Johannes Edmonds and Eckart Frahm identify three rulers who do not appear on the list but whose reigns can be reconstructed from other surviving evidence.
From Science Daily ● Aug. 26, 2026
Rome’s ancient rulers were among the first and most frequent combatants to cross and recross the Rhine in their futile quest to conquer Germania.
From The Wall Street Journal ● Aug. 21, 2026
Alienation between rulers and ruled even extended to matters of simple nomenclature: according to one modern authority on demotic-script documents, the natives studiously avoided referring to Alexandria in the language of their conquerors.
From "Circumference" by Nicholas Nicastro
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
