topsoil

noun

1. the fertile, upper part of the soil.

verb (used with object)

2. to cover (land) with topsoil.

noun

1. the surface layer of soil

verb (tr)

2. to spread topsoil on (land)
3. to remove the topsoil from (land)

n.

1836, from top (n.1) + soil (n.).

1. The upper portion of a soil, usually dark colored and rich in organic material. It is more or less equivalent to the upper portion of an A horizon in an ABC soil.

The thin, rich layer of soil where most nutrients for plants are found.