from
The Collaborative International Dictionary of English v.0.48
Horizontal \Hor`i*zon"tal\, a. [Cf. F. horizontal.]
1. Pertaining to, or near, the horizon. "Horizontal misty
air." --Milton.
[1913 Webster]
2. Parallel to the horizon; on a level; as, a horizontalline
or surface.
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3. Measured or contained in a plane of the horizon; as,
horizontal distance.
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{Horizontal drill}, a drilling machine having a horizontal
drill spindle.
{Horizontal engine}, one the piston of which works
horizontally.
{Horizontal fire} (Mil.), the fire of ordnance and small arms
at point-blank range or at low angles of elevation.
{Horizontal force} (Physics), the horizontal component of the
earth's magnetic force.
{Horizontal line} (Descriptive Geometry & Drawing), a
constructive line, either drawn or imagined, which passes
through the point of sight, and is the chief line in the
projection upon which all verticals are fixed, and upon
which all vanishing points are found.
{Horizontal parallax}. See under {Parallax}.
{Horizontal plane} (Descriptive Geometry), a plane parallel
to the horizon, upon which it is assumed that objects are
projected. See {Projection}. It is upon the horizontal
plane that the ground plan of the buildings is supposed to
be drawn.
{Horizontal projection}, a projection made on a plane
parallel to the horizon.
{Horizontal range} (Gunnery), the distance in a horizontal
plane to which a gun will throw a projectile.
{Horizontal water wheel}, a water wheel in which the axis is
vertical, the buckets or floats revolving in a horizontal
plane, as in most turbines.
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