Horizon

n. line where the sky appears to meet the Earth; view, range of operations or activities, purview; limit of the knowledge or interest of a person

For other uses of horizon, see Horizon (disambiguation) The horizon (Ancient Greek ὁ ὁρίζων, /ho horídzôn/, from ὁρίζειν, "to limit") is the line that separates earth from sky.More precisely, it is the line that divides all of the directions one can possibly look into two categories: those which intersect the Earth, and those which do not. At many locations, the true horizon is obscured by trees, buildings, mountains and so forth. The resulting intersection of earth and sky is instead known as the visible horizon.
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Noun
1. the line at which the sky and Earth appear to meet
(synonym) apparent horizon, visible horizon, sensible horizon, skyline
(hypernym) line
(part-holonym) perspective, linear perspective
2. the range of interest or activity that can be anticipated; "It is beyond the horizon of present knowledge"
(synonym) view, purview
(hypernym) scope, range, reach, orbit, compass, ambit
3. a specific layer or stratum of soil or subsoil in a vertical cross section of land
(hypernym) stratum
(hyponym) soil horizon
(part-holonym) profile
4. the great circle on the celestial sphere whose plane passes through the sensible horizon and the center of the Earth
(synonym) celestial horizon
(hypernym) great circle

n. horizon, outlook, vista

n. horizon, skyline, line where the sky appears to meet the Earth