1. Of or pertaining to the vertex; situated at the vertex, or highest
point; directly overhead, or in the zenith; perpendicularly above one.
Charity . . . is the vertical top of all religion.
Jer. Taylor.
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 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. (b) (Conic Sections) A right line drawn on the vertical plane,
and passing through the vertex of the cone. (c) (Surv.) The direction
of a plumb line; a line normal to the surface of still water. (d)
(Geom., Drawing, etc.) A line parallel to the sides of a page or sheet,
in distinction from a horizontal line parallel to the top or bottom. —
Vertical plane. (a) (Conic Sections) A plane passing through the vertex
of a cone, and through its axis. (b) (Projections) Any plane which
passes through a vertical line. (c) (Persp.) The plane passing through
the point of sight, and perpendicular to the ground plane, and also to
the picture. — 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.