horizontal

adjective hor·i·zon·tal \ ˌhȯr-ə-ˈzän-tᵊl , ˌhär- \

|Updated on: 13 Aug 2018

Definition of horizontal

1 a : 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 4

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horizontal

noun

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horizontality

play \ˌhȯr-ə-ˌzän-ˈta-lə-tē, ˌhär-\ noun

—

horizontally

play \ˌhȯr-ə-ˈzän-tᵊl-ē, ˌhär-\ adverb

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Recent Examples of horizontal from the Web

The past decade or so has seen a revolution in American energy production, however, led by techniques including hydraulic fracturing, or fracking, and horizontal drilling.

— david koenig, The Christian Science Monitor, "US expected to surpass Saudi Arabia, Russia as world's top oil producer," 12 July 2018
The last decade or so has seen a revolution in American energy production, however, led by techniques including hydraulic fracturing, or fracking, and horizontal drilling.

— david koenig, Anchorage Daily News, "US soon to leapfrog Saudis, Russia as top oil producer," 12 July 2018
The last decade or so has seen a revolution in American energy production, however, led by techniques including hydraulic fracturing, or fracking, and horizontal drilling.

— david koenig, chicagotribune.com, "U.S. soon to surpass Saudis, Russia as top oil producer," 11 July 2018
The trick was to combine horizontal drilling, enabling each well to fan out across a wide area, with industrial-scale hydraulic fracturing, or fracking, to crack up the innards of tight rock.

— jeffrey ball, Fortune, "Photographing The Permian Basin," 25 May 2018
From Oklahoma to North Dakota, companies are increasing investment in oil fields that fell out of favor several years ago, as $70-a-barrel crude prices make fracking and horizontal drilling economical in more places again.

— rebecca elliott, WSJ, "Shale Drillers Look Beyond Texas as Prices Rise," 14 May 2018
Putting together large blocks of land has become particularly important as horizontal drilling, which cuts across shale formations to tap multiple reservoirs, has become state-of-the-art.

— San Antonio Express-News, "Permian Basin gets cold shoulder," 19 Apr. 2018
Each of the boxes is designed with a sliding door that allow for easy access to the terraces and clusters of horizontal windows that look out onto the waves.

— liz stinson, Curbed, "Oceanfront modern house cascades down a rocky hill," 10 July 2018
One screen displays the progress as a 2-mile-long horizontal well is drilled 10,000 feet underground.

— christopher m. matthews, WSJ, "Oil’s New Technology Spells End of Boom for Roughnecks," 10 July 2018

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.