horizontal

adjective

hor·​i·​zon·​tal ˌhȯr-ə-ˈzän-tᵊl How to pronounce horizontal (audio)
ˌhär-
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 sense 4
horizontal noun
horizontality noun
horizontally adverb

Examples of horizontal in a Sentence

Recent Examples on the Web Typically, it is installed close to your water shut off valve in a horizontal pipe that is in line with your existing plumbing, before the pipes branch off to the rest of the home. Andrea Wurzburger, Better Homes & Gardens, 22 Nov. 2023 As a result, the windows are arranged in a horizontal expanse, providing panoramic views of the hills in Silver Lake and Echo Park. Marissa Gluck, Los Angeles Times, 20 Nov. 2023 At the bottom, past a spiral metal stairway, a long horizontal tunnel is shown, ending at a heavy door. Steve Hendrix, Washington Post, 19 Nov. 2023 Another 13 canisters of material from the dismantlement that are classified as greater than Class C waste will go into the horizontal storage facility. Rob Nikolewski, San Diego Union-Tribune, 16 Nov. 2023 Similarly, some of the parkour elements are a bit off—a move that’s meant to fling you up to higher ledges more often throws you sideways, while the move to leap horizontal gaps rarely connects—but level design is considerate enough to almost always have multiple ways to reach objectives. WIRED, 16 Nov. 2023 Close inspection also shows a faint horizontal line bisecting each Milky Way star, which is caused by light bending around a support strut of the telescope’s secondary mirror. Phil Plait, Scientific American, 3 Nov. 2023 The Sport Band has horizontal channels on both the inside and outside of the strap, with those on the interior helping to provide a bit of airflow so the strap doesn’t get sweaty and stuck to your skin. Tim Barribeau, wsj.com, 27 Oct. 2023 The face sports horizontal grooves on the face—a signature of the Nautilus series—as well as a day date window at 3 o’clock and a 12-hour mono counter at 6. Demetrius Simms, Robb Report, 25 Oct. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'horizontal.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

see horizon

First Known Use

1555, in the meaning defined at sense 1a

Time Traveler
The first known use of horizontal was in 1555

Dictionary Entries Near horizontal

Cite this Entry

“Horizontal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/horizontal. Accessed 4 Dec. 2023.

Kids Definition

horizontal

1 of 2 adjective
hor·​i·​zon·​tal
ˌhȯr-ə-ˈzänt-ᵊl,
ˌhär-
1
: of or relating to the horizon
2
: parallel to the horizon : level
3
: being on the same level
horizontally
-ᵊl-ē
adverb

horizontal

2 of 2 noun
: a horizontal line or plane

Medical Definition

horizontal

adjective
hor·​i·​zon·​tal ˌhȯr-ə-ˈzänt-ᵊl, ˌhär- How to pronounce horizontal (audio)
1
: relating to or being a transverse plane or section of the body
2
a
: 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
horizontally adverb

Legal Definition

horizontal

adjective
hor·​i·​zon·​tal ˌhȯr-ə-ˈzän-təl, ˌhär- How to pronounce horizontal (audio)
: relating to, directed toward, or consisting of individuals or entities of similar status or on the same level
horizontally adverb
Last Updated: - Updated example sentences
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