| Part of Speech | Definition | |
| Noun | 1. The top layer of a soil profile; usually contains humus.[Wordnet]. | |
Source: WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. | Top | |
Date "A-horizon" was first used in popular English literature: sometime before 1977. (references) |
Specialty Definition: A-horizon
| Domain | Definition | ||
| Mining | In a soil profile, the uppermost zone from which soluble salts and colloids have been leached and in which organic matter has accumulated. See also: B-horizon. (references) | ||
Source: compiled by the editor from various references; see credits. | Top | ||
