boul·​der | \ ˈbōl-dər How to pronounce boulder (audio) \
variants: or less commonly

Definition of boulder

 (Entry 1 of 2)

: a detached and rounded or much-worn mass of rock


geographical name
Boul·​der | \ ˈbōl-dər How to pronounce Boulder (audio) \

Definition of Boulder (Entry 2 of 2)

city northwest of Denver in north central Colorado population 97,385

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Other Words from boulder


bouldered \ ˈbōl-​dərd How to pronounce bouldered (audio) \ adjective
bouldery \ ˈbōl-​d(ə-​)rē How to pronounce bouldery (audio) \ adjective

Examples of boulder in a Sentence

Recent Examples on the Web: Noun Soldiers are taught how to lead their units over technically difficult and hazardous terrain, cutting paths through 4 feet of snow up a steep mountain face or scaling a field of boulders in scorching summer heat. Devin Dwyer, ABC News, "Inside Army Mountain Warfare School as Pentagon moves to expand elite training," 25 Feb. 2020 Scientists calculated that water ice could have the ability to form in the shadows of some of the boulders during the winter months. Jennifer Leman, Popular Mechanics, "While We Get Snow During Our Winter, Martians May Get Salty Water During Theirs," 13 Feb. 2020 The quality of snow in the landing zone, an east-facing embankment of boulders below the roadway, is often wet and dense — not ideal for cushioning the impact of a flying skier. Gregory Thomas,, "Ski-jumping over Highway 50? Here’s how Josh Daiek did it," 8 Feb. 2020 There, two men wielded a jackhammer in the middle of the jungle, tumbling a small landslide of boulders into the valley below. Chris Jones, WSJ, "A Rare Look at One of the World’s Most Isolated Mountain Treks," 4 Feb. 2020 An alternate landfall site about 5 miles closer to the LNG terminal site, preferred by several residents in the area, would cross a larger area of seafloor boulders, AGDC told FERC in a Dec. 23 response. Larry Persily, Anchorage Daily News, "Analysis: State awaits final EIS after answering Alaska LNG questions from federal regulators," 8 Jan. 2020 The two were off course on a crude route through the jumble of granite boulders in a basin of lakes when Hofer looked down and saw what looked like a bone. NBC News, "Skeleton identified as Japanese American artist who left California internment camp," 4 Jan. 2020 Moving each of those boulders would have required the strength of multiple people. Megan Gannon, Smithsonian, "Oldest Known Seawall Discovered Along Submerged Mediterranean Villages," 18 Dec. 2019 Many of the boulders Mr Bishton and his team put up in Sheffield used bulky, featureless volumes. The Economist, "For Olympic climbing’s route-setters, a blank wall is a canvas," 18 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'boulder.' 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 boulder


1607, in the meaning defined above

History and Etymology for boulder


short for boulder stone, from Middle English bulder ston, partial translation of a word of Scandinavian origin; akin to Swedish dialect bullersten large stone in a stream, from buller noise + sten stone

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Time Traveler for boulder

Time Traveler

The first known use of boulder was in 1607

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Statistics for boulder

Last Updated

21 Mar 2020

Cite this Entry

“Boulder.” Dictionary, Merriam-Webster, Accessed 3 Apr. 2020.

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More Definitions for boulder


How to pronounce Boulder (audio)

English Language Learners Definition of boulder

: a very large stone or rounded piece of rock


boul·​der | \ ˈbōl-dər \

Kids Definition of boulder

: a very large rounded piece of rock

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More from Merriam-Webster on boulder

Rhyming Dictionary: Words that rhyme with boulder

Spanish Central: Translation of boulder

Nglish: Translation of boulder for Spanish Speakers

Britannica English: Translation of boulder for Arabic Speakers Encyclopedia article about boulder

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