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Definition of horizon
1a : the line where the earth seems to meet the sky : the apparent junction of earth and sky
sailing toward the horizon
b : the great circle on the celestial sphere formed by the intersection of the celestial sphere with a plane tangent to the earth's surface at an observer's position — see azimuth illustration
c : range of perception or experience
broaden your horizons
d : something that might be attained
opening up new horizons in the field of cancer research
2a geology : a natural soil layer deposited at a particular time usually identified by distinctive fossils
b geology : any of the reasonably distinct layers of soil or its underlying material in a vertical section of land
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Time Traveler for horizon
The first known use of horizon was in the 14th century
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