[soil] 
| 1. | the portion of the earth's surface consisting of disintegrated rock and humus. |
| 2. | a particular kind of earth: sandy soil. |
| 3. | the ground as producing vegetation or as cultivated for its crops: fertile soil. |
| 4. | a country, land, or region: an act committed on American soil. |
| 5. | the ground or earth: tilling the soil. |
| 6. | any place or condition providing the opportunity for growth or development: Some believe that poverty provides the soil for crime. |
Material on the surface of the Earth on which plants can grow. (See topsoil.)
Note: Soil is produced by the weathering of rocks.
| soil (soil) Pronunciation Key
The loose top layer of the Earth's surface, consisting of rock and mineral particles mixed with decayed organic matter (humus), and capable of retaining water, providing nutrients for plants, and supporting a wide range of biotic communities. Soil is formed by a combination of depositional, chemical, and biological processes and plays an important role in the carbon, nitrogen, and hydrologic cycles. Soil types vary widely from one region to another, depending on the type of bedrock they overlie and the climate in which they form. In wet and humid regions, for example, soils tend to be thicker than they do in dry regions. See more at A horizon, B horizon, C horizon., See illustration at ABC soil. |