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:
Saudi Arabia's de facto ruler Crown Prince Mohammed bin Salman was expected to hold talks with Egypt's President Abdel Fattah al-Sisi Tuesday.
From Barron's ● Sep. 15, 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
Hungry for more, the people are drawn to a charismatic ruler promising to deliver.
From The Wall Street Journal ● Sep. 2, 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
They said he was the padeshah of pate a choux, the ruler supreme of rosewater and cream.
From "Everything Sad Is Untrue" by Daniel Nayeri
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
And we saw moments of unease between the rulers and those they rule.
From BBC ● Aug. 24, 2026
The post-apocalyptic, jazzy New Orleans-style “Hadestown,” written by Anaïs Mitchell, is a mythical love story that follows young lovers Orpheus and Eurydice and the rulers of the underworld, Hades and Persephone.
From Los Angeles Times ● Aug. 4, 2026
There is no sign that Kuwait’s rulers are planning a fundamental shift away from heavy reliance on the U.S. as their main security partner.
From The Wall Street Journal ● Jul. 31, 2026
Awed by its magnificence, fearful of the supernatural powers controlled by its priesthood, local rulers subordinated themselves.
From "1491" by Charles C. Mann
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.
