subsoil

American  

[suhb-soil] / ˈsʌbˌsɔɪl /

noun

1. the bed or stratum of earth or earthy material immediately under the surface soil.

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subsoil British  

/ ˈsʌbˌsɔɪl /

noun

1. 1. Also called: undersoil.  the layer of soil beneath the surface soil and overlying the bedrock

   2. ( as modifier )

      a subsoil plough

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verb

1. (tr) to plough (land) to a depth below the normal ploughing level and so break up the subsoil

subsoil Scientific  

/ sŭb′soil′ /

1. In an ABC soil, the B horizon. The term was formerly used to mean the layer of earth below the humus or surface soil.

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Other Word Forms

• subsoiler
  noun

Etymology

Origin of subsoil

First recorded in 1790–1800; sub- + soil ¹

Example Sentences

The request from the firm, KoBold Metals, was made about six months ago and involved access to a large quantity of data on the Congolese subsoil in order to digitise it, Ouvry explained.

From Barron's • Feb. 12, 2026

After scraping you’ll likely be left with subsoil, layers of clay or sand, that lack the life-giving nutrients plants require.

From Los Angeles Times • Apr. 24, 2025

Excavators are then used to dig out the top soil and subsoil.

From BBC • Oct. 19, 2024

Taiwan’s religious diversity and vitality forms a kind of subsoil of the self-governed island’s identity and values.

From New York Times • May 3, 2024

Much, too, depends on the nature of the subsoil, the quake’s duration, the frequency and severity of aftershocks, and the physical setting of the affected area.

From "A Short History of Nearly Everything" by Bill Bryson

Related Words

• clay
• coast
• dirt
• dust
• gravel
• land
• mud
• sand
• shore
• surface
• terrain
• turf