horizontal
Americanadjective
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at right angles to the vertical; parallel to level ground.
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flat or level.
a horizontal position.
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being in a prone or supine position; recumbent.
His bad back has kept him horizontal for a week.
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near, on, or parallel to the horizon.
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of or relating to the horizon.
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measured or contained in a plane parallel to the horizon.
a horizontal distance.
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(of material on a printed page, pieces on a game board, etc.) extending across, from the left to the right of the viewer.
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of or relating to a position or individual of similar status.
He received a horizontal promotion to a different department, retaining his old salary and title.
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Economics. of or relating to companies, affiliates, divisions, etc., that perform the same or similar functions or produce the same or similar products.
Through horizontal mergers the company monopolized its field.
noun
adjective
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parallel to the plane of the horizon; level; flat Compare vertical
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of or relating to the horizon
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measured or contained in a plane parallel to that of the horizon
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applied uniformly or equally to all members of a group
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economics relating to identical stages of commercial activity
horizontal integration
noun
Other Word Forms
Derived Forms
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horizontalitynoun
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horizontalnessnoun
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subhorizontalnessnoun
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subhorizontaladjective
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unhorizontaladjective
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horizontallyadverb
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subhorizontallyadverb
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unhorizontallyadverb
Inflected Forms
Nouns
Etymology
Origin of horizontal
1545–55; < Latin horizont- (stem of horizōn ) horizon + -al 1
Explanation
The opposite of vertical, something horizontal is arranged sideways, like a person lying down. When you sleep (unless you're a horse), your body is horizontal: horizontal things are parallel to the ground or running in the same direction as the horizon. If you stack books horizontally, then they're on their side. You hear a lot about horizontal lines in geometry: If you picture a square, the top and bottom lines are horizontal lines.
Vocabulary lists containing horizontal
Expressions and Equations
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Geometry - Introductory
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The Number System
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
The suit argues that owning the Golden Globes would “solidify a vertical and horizontal monopoly on the awards market.”
From Los Angeles Times ● Jul. 28, 2026
A Smithsonian Institution lab found that a flock of Brant and Canada geese “impacted” the rotor blades and the horizontal stabilizer.
From The Wall Street Journal ● Jul. 16, 2026
Unlike winds in the atmosphere, this mantle wind consists of a broad horizontal movement of hot, slowly flowing rock within Earth's mantle.
From Science Daily ● Jun. 28, 2026
Brazil's two-man midfield lacked the horizontal coverage a midfield three might have.
From BBC ● Jun. 15, 2026
Each tiny sign was perfectly formed, with little flags and short tails at the ends of each stroke, resting on invisible horizontal strings like pins perched on a clothesline.
From "The Reader" by Traci Chee
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“Florida Painting” etches red horizontals into a yellow expanse flanked by vivid green, while the two-panel “Space Age Relaxation” carves white lines and colored bars into brown fields.
From Washington Post ● Nov. 3, 2021
For the Academy, City Hall’s arresting vertical lines were tranquilized into calming horizontals.
From New York Times ● Apr. 4, 2020
The only strict horizontals and verticals that will be found are in the rectangular paintings' edges.
From Los Angeles Times ● Oct. 6, 2015
In the end, both vertical and horizontal turbines have their trade-offs, though horizontals are a more mature technology.
From Scientific American ● Aug. 18, 2011
She pointed to the dense thorny branches of a Blood Rose, cut and pinioned into cruel horizontals against the wall, yet still wild and heavy with dark red blooms.
From "How I Live Now" by Meg Rosoff
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.