hor·​i·​zon·​tal | \ ˌhȯr-ə-ˈzän-tᵊl How to pronounce horizontal (audio) , ˌhär- \

Definition of horizontal

1a : of or relating to the apparent junction of earth and sky : situated near the horizon
b : parallel to, in the plane of, or operating in a plane parallel to the horizon or to a baseline : level horizontal distance a horizontal engine
2 : relating to, directed toward, or consisting of individuals or entities of similar status or on the same level horizontal mergers horizontal hostility
3 medical : relating to or being transmission (as of a disease) by physical contact or proximity in contrast with inheritance Genes are normally inherited from parents, but they can also be inserted into a genome by viruses, plasmids, and other foreign agents—a phenomenon called horizontal transfer.— Stephan Reebs — compare vertical sense 4

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Other Words from horizontal

horizontal noun
horizontality \ ˌhȯr-​ə-​ˌzän-​ˈta-​lə-​tē How to pronounce horizontality (audio) , ˌhär-​ \ noun
horizontally \ ˌhȯr-​ə-​ˈzän-​tᵊl-​ē How to pronounce horizontally (audio) , ˌhär-​ \ adverb

Examples of horizontal in a Sentence

Recent Examples on the Web While the third quarter is typically the busiest, Halliburton noted stage counts — the sections of a horizontal well that get fracked — had declined each month. Liam Denning | Bloomberg, Washington Post, "Halliburton Writes the Script for Fracker Earnings," 21 Oct. 2019 Increased offshore drilling and substitution of natural gas, fracking (horizontal shale drilling), and conservation have all contributed to this benign trend, but it cannot be said that windmills and solar panels had much to do with it. Conrad Black, National Review, "Trump’s Economic Triumph," 26 Sep. 2019 Flame lengths can reach 300 feet, sometimes pushed horizontal by winds. AZCentral.com, "Of small communities across 11 states, more than 500 have a higher wildfire hazard potential than Paradise, Calif.," 23 July 2019 By combining fracking—or hydraulic fracturing—with horizontal drilling and other innovations, the fossil-fuel industry has managed to extract resources that were previously too costly to reach. Christina Nunez, National Geographic, "Fossil fuels, explained," 2 Apr. 2019 The building is actually buried into the grassy hillside, with Grier describing the project's scope as akin to building a horizontal skyscraper (also noting that the dome of St. Paul's Cathedral could fit under the distillery's rooftop). Jake Emen, USA TODAY, "The Macallan debuts sensational new Scotch distillery," 23 May 2018 Zawacki’s piece, which is closer to the Mystic River, is 146 feet by 21 feet in size and features a series of horizontal stripes in multicolored gradients. BostonGlobe.com, "But a fresh burst of color popped up this week in the longtime industrial corridor. Two bright murals, paid for by the casino, stretch along the walls of the power complex, offering a more inviting gateway between Boston and Everett, a city that has sometimes been self-conscious about its image.," 2 Nov. 2019 The wall was marked by three horizontal stripes of different heights, made by the paws of the hyenas jumping at the enclosure. Helen Sullivan, New York Times, "In Lebanon, the Hyena’s Main Fear Is Fear Itself," 30 Oct. 2019 In one loose sporty dress, horizontal Breton stripes gathered in waves at the hem creating the false impression of movement. San Diego Union-Tribune, "Quirks and provocations define Paris Fashion Week shows," 25 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'horizontal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of horizontal

1555, in the meaning defined at sense 1a

History and Etymology for horizontal

see horizon

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Time Traveler for horizontal

Time Traveler

The first known use of horizontal was in 1555

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Statistics for horizontal

Last Updated

3 Dec 2019

Cite this Entry

“Horizontal.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/horizontal. Accessed 8 December 2019.

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More Definitions for horizontal


How to pronounce horizontal (audio)

English Language Learners Definition of horizontal

: positioned from side to side rather than up and down : parallel to the ground


hor·​i·​zon·​tal | \ ˌhȯr-ə-ˈzän-tᵊl How to pronounce horizontal (audio) \

Kids Definition of horizontal

 (Entry 1 of 2)

: lying flat or level : parallel to the horizon

Other Words from horizontal

horizontally adverb



Kids Definition of horizontal (Entry 2 of 2)

: something (as a line or plane) that is parallel to the horizon


hor·​i·​zon·​tal | \ ˌhȯr-ə-ˈzänt-ᵊl, ˌhär- How to pronounce horizontal (audio) \

Medical Definition of horizontal

1 : relating to or being a transverse plane or section of the body
2a : relating to or being transmission (as of a disease) by physical contact or proximity in contrast with inheritance — compare vertical
b : of or relating to horizontal gene transfer

Other Words from horizontal

horizontally \ -​ᵊl-​ē How to pronounce horizontally (audio) \ adverb

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hor·​i·​zon·​tal | \ ˌhȯr-ə-ˈzän-təl, ˌhär- How to pronounce horizontal (audio) \

Legal Definition of horizontal

: relating to, directed toward, or consisting of individuals or entities of similar status or on the same level

Other Words from horizontal

horizontally adverb

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Comments on horizontal

What made you want to look up horizontal? Please tell us where you read or heard it (including the quote, if possible).


to constrict the range or activity of

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