Vertical

1. Of or pertaining to the vertex; situated at the vertex, or highest point; directly overhead, or in the zenith; perpendicularly above one.
2. Perpendicular to the plane of the horizon; upright; plumb; as, a vertical line.
Vertical angle (Astron. & Geod.),
an angle measured on a vertical circle, called an angle of elevation, or altitude, when reckoned from the horizon upward, and of depression when downward below the horizon.
Vertical anthers (Bot.),
such anthers as stand erect at the top of the filaments.
Vertical circle (Astron.),
an azimuth circle. See under Azimuth.
Vertical drill ,
an upright drill. See under Upright.
Vertical fire (Mil.),
the fire, as of mortars, at high angles of elevation.
Vertical leaves (Bot.),
leaves which present their edges to the earth and the sky, and their faces to the horizon, as in the Australian species of Eucalyptus.
Vertical limb ,
a graduated arc attached to an instrument, as a theodolite, for measuring vertical angles.
Vertical line . (a) (Dialing)
A line perpendicular to the horizon.
Vertical plane . (a) (Conic Sections)
A plane passing through the vertex of a cone, and through its axis.
Vertical sash ,
a sash sliding up and down. Cf. French sash, under 3d Sash.
Vertical steam engine ,
a steam engine having the crank shaft vertically above or below a vertical cylinder.

1. Vertical position; zenith.
2. (Math.) A vertical line, plane, or circle.
Prime vertical, Prime vertical dial .
See under Prime, a.