horizon

noun

ho·​ri·​zon hə-ˈrī-zᵊn How to pronounce horizon (audio)
1
a
: 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
2
a
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
c
anthropology : a cultural area or level of development indicated by separated groups of artifacts
horizonal 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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But when the music dissipated into quietude — recalling a boat drifting far off from shore, surrounded only by blue horizon — Guerrero guided the music with expansive ease. Hannah Edgar, Chicago Tribune, 21 June 2025 More important is an observing location with a clear, unobstructed view to the eastern or western horizon, if possible away from city lights — though light pollution makes zero difference to the planets and the moon. Jamie Carter, Forbes.com, 20 June 2025 Keeping big-name players for long is tougher because there are so many opportunities for them away from the court, broadening their career horizons. James Jackson, New York Times, 20 June 2025 Odyssey’s latest horizon image, captured May 2, indicates that Arsia Mons stands 12 miles high. Eric Lagatta, USA Today, 18 June 2025 See All Example Sentences for horizon

Word History

Etymology

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, in the meaning defined at sense 1a

Time Traveler
The first known use of horizon was in the 14th century

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Cite this Entry

“Horizon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/horizon. Accessed 2 Jul. 2025.

Kids Definition

horizon

noun
ho·​ri·​zon ˈhə-ˈrīz-ᵊn How to pronounce horizon (audio)
1
: the line where the earth or sea seems to meet the sky
2
: the limit or range of a person's outlook or experience
reading broadens our horizons
3
: a distinct layer of soil or its underlying material in a vertical section of land
horizonal
-ˈrīz-nəl How to pronounce horizon (audio)
-ᵊn-əl
adjective

More from Merriam-Webster on horizon

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