rul·​er | \ˈrü-lər \

Definition of ruler 

1 : one that rules specifically : sovereign

2 : a worker or a machine that rules paper

3 : a smooth-edged strip (as of wood or metal) that is usually marked off in units (such as inches) and is used as a straightedge or for measuring

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Other Words from ruler

rulership \ˈrü-​lər-​ˌship \ noun

Examples of ruler in a Sentence

a summit attended by a number of rulers from around the world This ruler shows inches and centimeters.

Recent Examples on the Web

The Klingons have hair again (fans did not care for the bald look), and the marvelous Michelle Yeoh returns as the former ruler of the Terran Empire, Philippa Georgiou—or perhaps an evil Mirror version. Jennifer Ouellette, Ars Technica, "New trailer for Star Trek: Discovery S2 gives us a young bearded Spock," 9 Oct. 2018 In lieu of a formal check-in desk, a standard bearer greets guests by militarily clicking his heels before leading them under a shower of rose petals and into the former ruler of Hyderabad’s neo-Palladian palace. Betsy Blumenthal, Condé Nast Traveler, "The Best Hotels in the World: 2018 Readers' Choice Awards," 9 Oct. 2018 The exquisite accessories were originally given to the Queen from the ruler of Bahrain for her wedding to Prince Philip in 1947, People reports. Erica Gonzales, Harper's BAZAAR, "Meghan Markle Wears Pearl Earrings Gifted from the Queen to the WellChild Awards," 4 Sep. 2018 Cheyenne Jackson Will play Hades (the ruler of the Underworld from Hercules) in the third installment. Tamara Fuentes, Seventeen, "Meet the Cast of "To All The Boys I've Loved Before" and Their Characters," 20 Aug. 2018 Mayr, then one of Europe’s dominant opera composers, was, in a way, the missing link between Mozart and Rossini, who would soon supplant him as the ruler of the opera realm. Heidi Waleson, WSJ, "‘The Dawn of Romantic Opera’ Review: Subtle, Playful Performances," 31 July 2018 But since Trump is now lavishing praise on the rulers of the world’s cruelest dictatorship, the party rank and file must follow suit: This is insane. Jonathan Chait, Daily Intelligencer, "The GOP Is a Trump Cult, Boasts Donald Trump Jr.," 14 June 2018 The bloodstock boom of the 1980s is widely attributed to Coolmore’s bidding wars with the rulers of Dubai, a rivalry whose bitterness eventually boiled over into a 12-year boycott of Coolmore by Sheikh Mohammed’s Godolphin racing. Tim Sullivan, The Courier-Journal, "Kentucky Derby hopeful Mendelssohn has the look and genes of a winner," 3 May 2018 Chadwick Boseman stars as the ruler of Wakanda and a masked warrior - the first Marvel film to feature a black superhero in the lead role. Steve Gardner, USA TODAY, "'Wakanda Forever' salute from 'Black Panther' showing up frequently in sports," 13 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ruler.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ruler

14th century, in the meaning defined at sense 1

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Statistics for ruler

Last Updated

5 Dec 2018

Look-up Popularity

Time Traveler for ruler

The first known use of ruler was in the 14th century

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More Definitions for ruler



English Language Learners Definition of ruler

: a person (such as a king or queen) who rules a country, area, group, etc.

: a straight piece of plastic, wood, or metal that has marks on it to show units of length and that is used to measure things


rul·​er | \ˈrü-lər \

Kids Definition of ruler

1 : a person (as a king or queen) having supreme power over a nation

2 : a straight strip (as of plastic, wood, or metal) with a smooth edge that is marked off in units and used for measuring or as a guide in drawing straight lines

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More from Merriam-Webster on ruler

Thesaurus: All synonyms and antonyms for ruler

Spanish Central: Translation of ruler

Nglish: Translation of ruler for Spanish Speakers

Britannica English: Translation of ruler for Arabic Speakers

Comments on ruler

What made you want to look up ruler? Please tell us where you read or heard it (including the quote, if possible).


to move with a clumsy heavy tread

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