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.
The most imposing presence in the great room is not a piece of furniture or work of art but a 7,500-pound limestone boulder nicknamed Jonas that was discovered on the property while the family was preparing the land for vines. — Kathryn O’Shea-Evans, Robb Report, 30 Aug. 2026 The writer compared the collapse of civil society to a boulder rolling downhill, crushing things in its path. — Kanis Leung, Christian Science Monitor, 30 Aug. 2026 Dozens of people were evacuated as the flooding swept large boulders, metal structures and other debris into the Colorado River, which runs through the Grand Canyon, the National Park Service said. — Emily St. Martin, Los Angeles Times, 30 Aug. 2026 This torrent was made up not just of water but was also loaded with silt, sand, gravel and giant boulders, which all moved together as a single fluid. — Sophie Tanno, CNN Money, 28 Aug. 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 1 Sep. 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

Last Updated: - Updated example sentences
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