noun boul·der \ˈbōl-dər\

: a very large stone or rounded piece of rock

Full Definition of BOULDER

:  a detached and rounded or much-worn mass of rock
boul·dered \-dərd\ adjective
boul·dery \-d(ə-)rē\ adjective

Variants of BOULDER

boul·der also bowl·der \ˈbōl-dər\

Origin of BOULDER

short for boulder stone, from Middle English bulder ston, part 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: 1617

Other Geology Terms

anthracite, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale

Rhymes with BOULDER


geographical name Boul·der \ˈbōl-dər\

Definition of BOULDER

city N cen Colorado pop 97,385
BOULDER Defined for Kids


noun boul·der \ˈbōl-dər\

Definition of BOULDER for Kids

:  a very large rounded piece of rock
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