C horizon

American  

noun

1. the layer in a soil profile below the B horizon and immediately above the bedrock, consisting chiefly of weathered, partially decomposed rock.

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C horizon British  

noun

1. the layer of a soil profile immediately below the B horizon and above the bedrock, composed of weathered rock little affected by soil-forming processes

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C horizon Scientific  

1. In ABC soil, the lowermost zone, consisting mainly of unconsolidated, weathered rock fragments. By comparison with the A and B horizons, the C horizon is relatively unaffected by the processes of soil formation and therefore does not exhibit as much internal layering.

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Etymology

Origin of C horizon

First recorded in 1930–35