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rimrock

American  
[rim-rok] / ˈrɪmˌrɒk /

noun

Geology.
  1. rock forming the natural boundary of a plateau or other rise.

  2. bedrock forming the natural boundary of a placer or of a gravel deposit.


rimrock British  
/ ˈrɪmˌrɒk /

noun

  1. rock forming the boundaries of a sandy or gravelly alluvial deposit

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of rimrock

An Americanism dating back to 1855–60; rim + rock 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Get away from those sticky oilmen who can hear a dollar bill fall on the rimrock — men who would watch the world burn to increase their profits.

From Washington Post • May 23, 2018

The Deschutes’s native rainbow trout take notice of the salmon flies’ arrival among the river’s rimrock walls.

From New York Times • May 11, 2013

Barely 10 a.m., yet it seemed the entire sector--a classic Western landscape of rimrock, saguaro and sage--was already swimming with fishy activity.

From Time Magazine Archive

New England's sumac was already scarlet; and below the snow-dusted rimrock of the high Rockies, aspen gleamed like brass.

From Time Magazine Archive

He stood on the edge of the rimrock and looked down below: the canyons and valleys were thick powdery black; their variations of height and depth were marked by a thinner black color.

From "Ceremony:" by Leslie Marmon Silko