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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.

The spat is emerging as a source of frustration in Congo, which already holds a historic grudge with its old colonial ruler.

From The Wall Street Journal • Mar. 28, 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

“Only those nations ruled by kings or dictators display the image of their sitting ruler on the coins of the realm.”

From The Wall Street Journal • Mar. 19, 2026

Madagascar's military ruler Col Michael Randrianirina has dissolved the government unexpectedly, dismissing the prime minister and the entire cabinet, according to a statement from his spokesperson.

From BBC • Mar. 10, 2026

Which is how I came to be here, about to try to find a monarch willing to back a ruler other than Balekin.

From "The Cruel Prince" by Holly Black

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.