noun[mass noun] chiefly North American
- An outcrop of resistant rock forming a margin to a gravel deposit, especially one forming a cliff at the edge of a plateau: archetypal cowboy terrain—tableland, rimrock, canyons [as modifier]: a gap in the plateau’s rimrock cliffs [count noun]: they stopped for lunch on a rimrock overlooking a streamMore example sentences
- The ranch's riding trails head off through open forest toward the Marble Mountain foothills or along rimrock canyon edges with bracing views of Fraser River and the Chilcotin area.
- As the trio neared the top of the ridge, they found their way blocked by a wall of rimrock.
- As the mountains pushed up, the river cut deep canyons, the rimrock of which shows 400 million years of erosion.
More definitions of rimrockDefinition of rimrock in:
- The US English dictionary