Angle

Symbol for the Semi-Square

Two types of angles are commonly meant in astrology.

A line drawn from the Medium Coeli and Imum Coeli creates an "up-down" or south-north axis.
A line drawn from the Ascendant to the Descendant creates an east-west axis. The resulting cross as well as each of its four points, are called the chart angles, or cardinal points.

Aspects are also described in terms of angles, such as the square of 90 degrees and the trine of 120 degrees.
The distance between any two points on the horoscope, whether it forms a major aspect or not, is expressed in degrees, termed the angular distance.