[ hawr-uh-zon-tl, hor- ]
See synonyms for: horizontalhorizontalshorizontally on Thesaurus.com

  1. at right angles to the vertical; parallel to level ground.

  2. flat or level: a horizontal position.

  1. being in a prone or supine position; recumbent: His bad back has kept him horizontal for a week.

  2. near, on, or parallel to the horizon.

  3. of or relating to the horizon.

  4. measured or contained in a plane parallel to the horizon: a horizontal distance.

  5. (of material on a printed page, pieces on a game board, etc.) extending across, from the left to the right of the viewer.

  6. 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.

  7. 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.

  1. anything horizontal, as a plane, direction, or object.

Origin of horizontal

1545–55; <Latin horizont- (stem of horizōn) horizon + -al1

Other words from horizontal

  • hor·i·zon·tal·i·ty [hawr-i-zon-tal-i-tee, hor-], /ˌhɔr ɪ zɒnˈtæl ɪ ti, ˌhɒr-/, hor·i·zon·tal·ness, noun
  • hor·i·zon·tal·ly, adverb
  • sub·hor·i·zon·tal, adjective
  • sub·hor·i·zon·tal·ly, adverb
  • sub·hor·i·zon·tal·ness, noun
  • un·hor·i·zon·tal, adjective
  • un·hor·i·zon·tal·ly, adverb

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use horizontal in a sentence

British Dictionary definitions for horizontal


/ (ˌhɒrɪˈzɒntəl) /

  1. parallel to the plane of the horizon; level; flat: Compare vertical (def. 1)

  2. of or relating to the horizon

  1. measured or contained in a plane parallel to that of the horizon

  2. applied uniformly or equally to all members of a group

  3. economics relating to identical stages of commercial activity: horizontal integration

  1. a horizontal plane, position, line, etc

Derived forms of horizontal

  • horizontality or horizontalness, noun
  • horizontally, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012