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.
After heavy rain, swollen streams can burst their banks, carrying mud and boulders down the mountainsides. NPR, 4 Apr. 2026 Violent, volcanic explosions some 30 million years ago (after dinosaurs went extinct) created the sheer rock faces and fields of boulders that make the region's geography so unique. Lauren Villagran, USA Today, 1 Apr. 2026 The fatal fall happened just one day after two people were injured in the park when boulders crashed onto their car on Little River Road, park officials said. Mark Price, Charlotte Observer, 31 Mar. 2026 Over the course of six inconceivably traumatic days, Caldwell and three friends were forcibly marched and starved, shoved under boulders to evade detection, and made to watch their kidnappers execute members of the rival Kyrgyz Army at point-blank range. Namir Khaliq, Big Think, 31 Mar. 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

Browse Nearby Words

Cite this Entry

“Boulder.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/boulder. Accessed 6 Apr. 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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