| Subsoil 1. (n.) The bed, or stratum, of earth which lies immediately beneath the surface soil. 2. (v. t.) To turn up the subsoil of. Thesaurus Entries acres, alluvion, alluvium, arable land, clay, clod, crust, dirt, dry land, dust, earth, freehold, glebe, grassland, ground, land, landholdings, lithosphere, marginal land, marl, mold, real estate, real property, region, regolith, sod, soil, subaerial deposit, terra, terra firma, terrain, territory, the country, topsoil, woodland |