Boulder vs. Bedrock — What's the Difference?

In geology (Udden–Wentworth scale), a boulder is a rock fragment with size greater than 256 millimetres (10.1 in) in diameter. Smaller pieces are called cobbles and pebbles.

Bedrock in geology is solid rock that lies under loose softer material (regolith) within the crust of the Earth or another terrestrial planet.

A large rounded mass of rock lying on the surface of the ground or embedded in the soil.

The solid rock that underlies loose material, such as soil, sand, clay, or gravel.

A large mass of stone detached from the surrounding land.

The very basis; the foundation

(geology) A particle greater than 256 mm in diameter, following the Wentworth scale

The lowest point

A large marble, in children's games.

The solid rock that exists at some depth below the ground surface. Bedrock is rock "in place", as opposed to material that has been transported from another location by weathering and erosion.

(climbing) A session of bouldering; involvement in bouldering.

(figurative) A basis or foundation.

To engage in bouldering.

To establish on a solid foundation.

Same as Bowlder.

Solid unweathered rock lying beneath surface deposits of soil

A large smooth mass of rock detached from its place of origin

Principles from which other truths can be derived;

A town in north central Colorado; Rocky Mountains resort center and university town