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

Langkilde said the radar is detecting the lowest portions of the walls and foundations, which were made with large boulders that were often left in place when medieval buildings were torn down. — Andrea Margolis, FOXNews.com, 7 Sep. 2026

Few character intros in movie history are better than Indiana Jones snagging that golden idol before being promptly chased by a giant boulder and a tribe of blowdart-wielding warriors. — Frank Deruggiero, Entertainment Weekly, 3 Sep. 2026

The park on the first block would feature various terraces, a boulder crawl, a plaza area, a picnic area, a nature play area, swings and other features. — Chris Higgins, Kansas City Star, 2 Sep. 2026

But in reality, the carving occurs in fits and spurts, when floods carry huge boulders that gouge out streambeds and jam cobbles into the bedrock. — Stephanie Pappas, Scientific American, 1 Sep. 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