Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun horizontal

1 sense of horizontal

Sense 1
horizontal -- (something that is oriented horizontally)
       => orientation -- (position or alignment relative to points of the compass or other specific directions)

Antonyms of adj horizontal

1 sense of horizontal

Sense 1
horizontal (vs. vertical) (vs. inclined) -- (parallel to or in the plane of the horizon or a base line; "a horizontal surface")

vertical (vs. inclined) (vs. horizontal), perpendicular -- (at right angles to the plane of the horizon or a base line; "a vertical camera angle"; "the monument consists of two vertical pillars supporting a horizontal slab"; "measure the perpendicular height")
        => plumb -- (exactly vertical; "the tower of Pisa is far out of plumb")
        => upended -- (turned up on end)
        => upright, unsloped -- (in a vertical position; not sloping; "an upright post")
inclined (vs. horizontal) (vs. vertical) -- (at an angle to the horizontal or vertical position; "an inclined plane")
        => atilt, canted, leaning, tilted, tipped -- (departing or being caused to depart from the true vertical or horizontal; "the leaning tower of Pisa"; "the headstones were tilted")
        => aslant, aslope, diagonal, slanted, slanting, sloped, sloping -- (having an oblique or slanted direction)
        => high-pitched -- (set at a sharp or high angle or slant; "a high-pitched roof")
        => low-pitched -- (set at a low angle or slant; "a low-pitched roof")
        => monoclinal -- (of a geological structure in which all strata are inclined in the same direction)
        => pitched -- (set at a slant; "a pitched rather than a flat roof")
        => salient (postnominal) -- (represented as leaping (rampant but leaning forward))
        => sidelong -- (inclining or directed to one side; "moved downward in a sidelong way" - Bram Stoker)
        => skew, skewed -- (having an oblique or slanting direction or position; "the picture was skew")

Similarity of adj horizontal

1 sense of horizontal

Sense 1
horizontal (vs. vertical) (vs. inclined) -- (parallel to or in the plane of the horizon or a base line; "a horizontal surface")
       => crosswise -- (in the shape of (a horizontal piece on) a cross)
       => flat -- (horizontally level; "a flat roof")
       => level -- (being on a precise horizontal plane; "a billiard table must be level")
       => naiant, swimming -- (applied to a fish depicted horizontally)