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

Intense downpours that far exceeded the forecast created massive debris flows in Montecito, a coastal town east of Goleta, burying homes and cars under mud and boulders. Howard Blume,, "Another night of terror and calamity for Santa Barbara County as new destructive fire sweeps through," 8 July 2018 Also, avoid high and open areas (like boulders or fields), tall objects like trees, bodies of water, and metal. Carolyn L. Todd, SELF, "14 Essential Hiking Safety Tips You Should Always Follow," 10 May 2019 Milling bounced off a boulder and slid an additional 400 feet down the snowy slope before coming to a stop, according to ABC News. Don Sweeney, sacbee, "A deaf hiker fell 700 feet down an Alaska mountain. Then a husky named Nanook found her," 1 July 2018 Swimmers have their own beach of dark sand with some protruding boulders at the pier., "The 20 best beaches to visit in New England," 2 May 2018 Lawrence is an absolute monster—a boulder to move against the run, with the athletic potential to become a high-end distrupter in the passing game. Albert Breer,, "2019 NFL Mock Draft: A Very Early Look at the Potential Top 10 Picks," 11 July 2018 The biggest fear is that the summit will explode and blast huge boulders into the air. David Montero,, "New fissure prompts more evacuations near Kilauea volcano," 14 May 2018 The car went through a stop sign, up onto a curb, and into a boulder in front of a yard, police said. Jackson Cote,, "Elderly couple die after car crash in Worcester," 5 July 2018 The offender shattered the window on the front door with a boulder to gain entry. Staff Report, Daily Southtown, "Southland police blotter," 3 July 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

14 Jun 2019

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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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

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).


to take the place or position of

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