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:
But as the Lord of Darkness, the massively built ruler of the underworld in Ridley Scott’s underappreciated fantasy, Curry embodied a paradox.
From Salon ● Aug. 26, 2026
Edmonds and Frahm argue that this long-standing puzzle can be explained by adding another ruler to the royal sequence.
From Science Daily ● Aug. 26, 2026
The agreement for the "colossal" project was signed during a two-day visit to France by Saudi Arabia's de facto ruler, Crown Prince Mohammed bin Salman, said President Emmanuel Macron's office.
From Barron's ● Aug. 24, 2026
It advocated for greater freedoms and rule of law even as those notions fell increasingly out of favor with a populace willing to embrace a strongman ruler to end the post-Soviet economic malaise.
From The Wall Street Journal ● Aug. 22, 2026
They are supposed to climb to the top of the mountain to meet with the Mountain Spirit, to gain his wisdom and approval, and, by doing so, to prove they are the fated ruler.
From "When the Sea Turned to Silver" by Grace Lin
“Their maximalism will contribute to their isolation in the long run,” said Behnam Ben Taleblu, an Iran expert at the Foundation for Defense of Democracies, a policy organization that opposes Iran’s rulers.
From The Wall Street Journal ● Aug. 5, 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
Its carefully planned streets and advanced brick drainage systems indicate that resources were directed toward shared infrastructure rather than monuments celebrating rulers or religious elites.
From Science Daily ● Jul. 30, 2026
Health care had long been a point of pride for Cuba's communist rulers, who were able to offer free care and highly subsidised medicines for all.
From Barron's ● Jul. 29, 2026
His mind had a hard time grasping names of places, or remembering countries or rulers, how the world was organized.
From "The Maze Runner" by James Dashner
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.
