Noun | 1. | horizon - the line at which the sky and Earth appear to meet |
2. | horizon - the range of interest or activity that can be anticipated; "It is beyond the horizon of present knowledge" | |
3. | horizon - a specific layer or stratum of soil or subsoil in a vertical cross section of land | |
4. | horizon - the great circle on the celestial sphere whose plane passes through the sensible horizon and the center of the Earth Synonyms: celestial horizon |