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 illustrationc : 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 fossilsb geology : any of the reasonably distinct layers of soil or its underlying material in a vertical section of landc anthropology : a cultural area or level of development indicated by separated groups of artifacts
horizonalplay \hə-ˈrī-zən-əl\ adjective
Examples of horizon in a sentence
We sailed toward the horizon.
The sun rose slowly over the eastern horizon.
These discoveries have opened up new horizons in the field of cancer research.
Origin and Etymology of horizon
Middle English orizon, from Late Latin horizont-, horizon, from Greek horizont-, horizōn, from present participle of horizein to bound, define, from horos boundary; perhaps akin to Latin urvum curved part of a plow
First Known Use: 14th century
HORIZON Defined for English Language Learners
Definition of horizon for English Language Learners
the horizon : the line where the earth or sea seems to meet the sky
: the limit or range of a person's knowledge, understanding, or experience
: the limit of what is possible in a particular field or activity
HORIZON Defined for Kids
Definition of horizon for Students
1 : the line where the earth or sea seems to meet the sky
2 : the limit of a person's outlook or experience <Reading broadens our horizons.>
Seen and Heard
What made you want to look up horizon? Please tell us where you read or heard it (including the quote, if possible).