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Synonyms

ruler

American  
[roo-ler] / ˈru lər /

noun

  1. a person who rules or governs; sovereign.

  2. 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.

  3. a person or thing that rules paper, wood, etc.

  4. 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.
ruler British  
/ ˈruːlə /

noun

  1. a person who rules or commands

  2. 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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • subruler noun
  • underruler noun

Etymology

Origin of ruler

Middle English word dating back to 1325–75; rule, -er 1

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.

Built in 1837 by former Awadh ruler Muhammad Ali Shah, the site once served not just the elite, but the public too.

From BBC • Mar. 28, 2026

At the time of the massacre, Diakité was commander of the presidential guard and a close ally of Guinea's then military ruler, Moussa Dadis Camara.

From BBC • Mar. 26, 2026

"Only those nations ruled by kings or dictators display the image of their sitting ruler on the coins of the realm," he said.

From Barron's • Mar. 20, 2026

Iran’s political and religious establishments have rallied around the new ruler, with officials publicly pledging their allegiance.

From The Wall Street Journal • Mar. 10, 2026

And there is the place named after its ruler: Hel, where the dead go who did not die bravely in battle.

From "Norse Mythology" by Neil Gaiman

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.