boulder

noun

boul·​der ˈbōl-dər How to pronounce boulder (audio)
variants or less commonly bowlder
: a detached and rounded or much-worn mass of rock
bouldered
ˈbōl-dərd How to pronounce boulder (audio)
adjective
bouldery
ˈbōl-d(ə-)rē How to pronounce boulder (audio)
adjective

Examples of boulder in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Anne said the climb involved seemingly endless boulders, sidehilling and scrambling. — Harllie Stevenson, Idaho Statesman, 20 Oct. 2026 Living shorelines, such as those along the Orange and San Diego county coasts, involve piling sand atop boulders or smaller stones and covering the berms with vegetation. — Steve Lopez, Los Angeles Times, 17 Oct. 2026 The 50-ton boulder was found about 30 feet below the surface of the airfield while crews excavated the South Detention Basin, a stormwater management facility, as part of the ORDNext terminal expansion project. — Sara Tenenbaum, CBS News, 16 Oct. 2026 An Oregon man who was trapped under a boulder about the size of a Volkswagen Beetle used his wireless earbuds to place a call for help, the police and the man’s mother said. — Ishani Desai, New York Times, 4 Oct. 2026 See All Example Sentences for boulder

Word History

Etymology

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

First Known Use

1607, in the meaning defined above

Time Traveler
The first known use of boulder was in 1607

Rhymes for boulder

See All Rhymes for boulder

Browse Nearby Words

boulangerite
boulder
Boulder
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Cite this Entry

“Boulder.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/boulder. Accessed 27 Oct. 2026.

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Kids Definition

boulder

noun
boul·​der ˈbōl-dər How to pronounce boulder (audio)
: a large detached and rounded or worn mass of rock

Geographical Definition

Boulder

geographical name

Boul·​der ˈbōl-dər How to pronounce Boulder (audio)
city northwest of Denver in north central Colorado

More from Merriam-Webster on boulder

Britannica.com: Encyclopedia article about boulder

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