rul·​er | \ ˈrü-lər How to pronounce ruler (audio) \

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 How to pronounce rulership (audio) \ 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

On Saturday night, Israeli officials said their aircraft hit several military targets belonging Gaza’s Hamas rulers, after militants used a drone to drop a bomb on the Israeli side of the Gaza-Israel perimeter fence earlier in the day. Fox News, "Rocket fired at southern Israel from Gaza following Israeli aircraft strike for drone 'attack'," 9 Sep. 2019 Second, as a legitimate if increasingly flawed ruler from independence in 1980 until his humiliating defeat in a constitutional referendum in 2000. The Economist, "Robert Mugabe leaves a bitter legacy," 7 Sep. 2019 Researchers from Nanyang Technological University in Singapore have developed an optical ruler that uses light to measure all the way down to the nanoscale. Courtney Linder, Popular Mechanics, "Crazy Powerful Optical Ruler Measures All the Way Down to the Nanoscale," 6 Sep. 2019 This new tyrannosaur became Timurlengia euotica in honor of the 14th century Central Asian ruler Timur Leng (Tamerlane or Timur the Lame). Hans-dieter Sues, Smithsonian, "How to Discover Dinosaurs," 3 Sep. 2019 In the meantime, the rogue ruler sidestepped taxation laws and whipped up hatred among his subjects, sentiments that fueled a civil war and his eventual execution for treason. Erin Blakemore, National Geographic, "The dramatic history of prorogation in British parliament," 29 Aug. 2019 This is a current trend evident in the closeness of leaders like Trump and more repressive rulers like Vladimir Putin of Russia or Viktor Orban of Hungary. David Mednicoff, The Conversation, "Why increasing Arab-Israeli closeness matters," 29 Aug. 2019 Manafort’s close ties to Russia’s authoritarian ruler match Trump’s own praise for Putin. Dan Mclaughlin, National Review, "Mitch McConnell Didn’t Stop Obama from Doing Anything about Russia in 2016," 2 Aug. 2019 By contrast, a general supply list for grades six through eight, posted on CMSD’s website, includes only the basics -- glue sticks, ruler, pencils, pens, paper, folders, notebooks, etc. Leila Atassi,, "Is it just me, or does this Cleveland public school supply list seem excessive?: Leila Atassi," 22 Aug. 2019

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

12 Sep 2019

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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 How to pronounce ruler (audio) \

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

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miscellaneous remnants or debris

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