the line or circle that forms the apparent boundary between earth and sky.
2.
Astronomy.
a.
the small circle of the celestial sphere whose plane is tangent to the earth at the position of a given observer, or the plane of such a circle (sensible horizon).
b.
Also called rational horizon.the great circle of the celestial sphere whose plane passes through the center of the earth and is parallel to the sensible horizon of a given position, or the plane of such a circle (celestial horizon).
3.
the limit or range of perception, knowledge, or the like.
4.
Usually, horizons.the scope of a person's interest, education, understanding, etc.: His horizons were narrow.
5.
Geology. a thin, distinctive stratum useful for stratigraphic correlation.
6.
any of the series of distinctive layers found in a vertical cross section of any well-developed soil.
Origin: 1540–50; < L horizōn < Gk horízōn (kýklos) bounding (circle), equiv. to horíz(ein) to bound, limit + -ōn prp. suffix (nom. sing.); r. ME orizonte < MF < L horizontem, acc. of horizōn
A specific position in a stratigraphic column, such as the location of one or more fossils, that serves to identify the stratum with a particular period.
A specific layer of soil or subsoil in a vertical cross-section of land.
Geology
A specific position in a stratigraphic column, such as the location of one or more fossils, that serves to identify the stratum with a particular period.
A specific layer of soil or subsoil in a vertical cross-section of land.
Archaeology A period during which the influence of a particular culture spread rapidly over a defined area.
sensible horizon (sěn'sə-bəl) Pronunciation Key
The plane of an observer's position lying at a right angle to the line formed by the observer's zenith and nadir. The plane of the sensible horizon is parallel to the plane of the observer's celestial horizon but is tangential to the Earth's surface rather than passing through the Earth's center. Both the celestial and sensible horizons change with the observer's position. Compare celestial horizon.
[huh-rahy-zuh