boulder

noun

boul·​der ˈbōl-dər 

variants or less commonly bowlder

: a detached and rounded or much-worn mass of rock

bouldered

ˈbōl-dərd 

adjective

bouldery

ˈbōl-d(ə-)rē 

adjective

Examples of boulder in a Sentence

Recent Examples on the Web

The driver then hit a large landscape boulder and collided with the base of a streetlight on the east side of the service road, police said. — Shambhavi Rimal, Fort Worth Star-Telegram, 13 July 2026

The river dropped 60 feet between boulders in a series of falls and continued downstream in a dangerous half mile of holes and boils. — John Todd, Outdoor Life, 9 July 2026

In 2021, Extra reported that Pettet was pinned under a boulder in a freak accident, later undergoing surgery to replace her shoulder and rotator cuff. — Jack Smart, PEOPLE, 9 July 2026

Deploying nets and traps from armored breakwalls and along shoreline boulders, their efforts weren't successful in 2024. — Keith Matheny, Freep.com, 3 July 2026

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

Rhymes for boulder

• bolder
• bowlder
• colder
• folder
• golder
• holder
• molder
• moulder
• older
• polder
• shoulder
• beholder

Kids Definition

boulder

noun

boul·​der ˈbōl-dər 

: a large detached and rounded or worn mass of rock

Geographical Definition

Boulder

geographical name

Boul·​der ˈbōl-dər 

city northwest of Denver in north central Colorado population 97,385