soil horizon(n = noun.location) - a layer in a soil profile;
is a kind of horizon
is a part of profile
has particulars: a-horizon, a horizon, b-horizon, b horizon, c-horizon, c horizon

a horizon, alkali soil, alluvial soil, apparent horizon, artificial horizon, b horizon, bog soil, c horizon, celestial horizon, chernozemic soil, desert soil, desertic soil, event horizon, free soil party, geological horizon, gilgai soil, gumbo soil, gyro horizon, horizon, leaf soil, night soil, podsol soil, podsolic soil, podzol soil, prairie soil, regur soil, residual soil, sensible horizon, soil, soil bank, soil conditioner, soil conservation, soil erosion, soil pipe, soil profile, soil science, surface soil, tundra soil, visible horizon