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 adjective
bouldery 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 shore now alternated between open sandy or rocky beaches and jumbled boulders ranging from a foot to many feet in diameter. Marc Terziev, Outdoor Life, 25 June 2026 When first responders got to the scene, the boulder was still on top of Frasch. Jesse Sarles, CBS News, 25 June 2026 Reduce The Amount Of Hardscape Large boulders, concrete paths, and driveways that are exposed to direct sun all day increase daytime and overnight temperatures of the soil nearby. Mary Marlowe Leverette, Southern Living, 24 June 2026 Apollo 11 had to dodge a boulder field. Leonard David, Space.com, 22 June 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

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Cite this Entry

“Boulder.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/boulder. Accessed 28 Jun. 2026.

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 population 97,385

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