Other forms: boulders

A boulder is a rock — a big one.

Scientists often think of a boulder in more technical terms than we do. They use the word to describe not just a big rock, but a rock that some natural force — a river, a glacier or the like — has moved from its original location to its present one. A good way to remember all this is to think of Boulder, a city in Colorado that stands in the middle of the Rocky Mountains, and is, no doubt, full of boulders.

Definitions of boulder
  1. noun
    a large smooth mass of rock detached from its place of origin
    synonyms: bowlder
    see moresee less
    Plymouth Rock
    a boulder in Plymouth supposed to be where the Pilgrims disembarked from the Mayflower
    glacial boulder
    a boulder that has been carried by a glacier to a place far distant from its place of origin
    river boulder
    a boulder that has been carried by a river to a place remote from its place of origin
    shore boulder
    a boulder found on a shore remote from its place of origin
    type of:
    rock, stone
    a lump or mass of hard consolidated mineral matter




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