noun

1. A vertex or zenith.

2. A vertical geometrical figure; a perpendicular.

3. An individual slat in a set of vertical blinds.

adjective

1. Standing, pointing, or moving straight up or down; along the direction of a plumb line; perpendicular to something horizontal.

2. In a two-dimensional Cartesian co-ordinate system, describing the axis y oriented normal (perpendicular, at right angles) to the horizontal axis x.

3. In a three-dimensional co-ordinate system, describing the axis z oriented normal (perpendicular, orthogonal) to the basic plane xy.

Synonyms: harmonic