boul·der | \ˈbōl-dər \
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 \

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 \ adjective
bouldery \ˈbōl-d(ə-)rē \ adjective

Examples of boulder in a Sentence

Recent Examples on the Web: Noun

In one photo from the 1970s, Ali is standing proudly atop the Liston boulder, gazing out at a spectacular vista of the Appalachian range, a view mature hillside trees now obscure. Frank Fitzpatrick,, "Muhammad Ali's secluded Pa. camp and the fight to save it, led by John Madden's son," 3 July 2018 The bulldozers and backhoes that Hernandez would need to uncover his parents are at the bottom of the hill, concentrating on re-opening a highway blocked by a mountain of ash and boulders. Mark Stevenson, Fox News, "At Guatemala volcano, families left on own to keep searching," 8 June 2018 Crews in heavy equipment reset the trackbed after removing huge blocks of river ice and shoving boulders and rocks back in place, said Sullivan. Alex Demarban, Anchorage Daily News, "Alaska Railroad back on track after repair of ice-jam damage," 16 May 2018 In the darkness and high seas, several other lifeboats and rafts drifted away toward the Mull of Oa, the rugged, southern shore of Islay, where 600-foot cliffs and offshore jagged rocks and boulders created especially treacherous breakers. Richard Kurin, Smithsonian, "A Hundred-Year-Old Handmade American Flag Flies Home… to Scotland," 30 Apr. 2018 As crews clean up the debris and mud, cars, boats, boulders and parts of tree clog roadways and bridges. David Caraccio, sacbee, "This is what the mud cleanup in Montecito is looking like | The Sacramento Bee," 18 Jan. 2018 The terrain varies from one area to the next — from sandy bottom to deep mud to boulders the size of a house. Richard C. Paddock,, "Thai cave rescue is pushing the abilities of divers to the edge," 6 July 2018 One of the most magical spots is the Bois de la Chaise, a fragrant pine wood dotted with boulders and even a menhir, a standing stone erected in prehistoric times. Mary Winston Nicklin, Condé Nast Traveler, "The Small Island Where the Tour de France Begins Is Actually a Vacationer's Paradise," 3 July 2018 At its southern edge, the vast body deposited tons of rocky debris — from sand and pebbles to boulders the size of school buses. William J. Broad, New York Times, "How the Ice Age Shaped New York," 5 June 2018

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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Statistics for boulder

Last Updated

4 Oct 2018

Look-up Popularity

Time Traveler for boulder

The first known use of boulder was in 1607

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More Definitions for boulder



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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Comments on boulder

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


evasion of direct action or statement

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