Semi-Square

SEM-ee skwair

Definition

A semi-square is an aspect of 45° — two planets one-eighth of the zodiac circle apart (360 ÷ 8 = 45). It belongs to the eighth-harmonic family, alongside the square (90°) and the sesquiquadrate (135°), and links signs that sit one and a half signs apart.

In Tradition

Most Western astrologers read the semi-square as a source of mild friction, irritability, and small tension that calls for minor adjustment. Many describe it as a gentler version of the square — some even nickname it the 'nuisance' aspect.

In Practice

Astrologers tend to take a semi-square seriously when it is tight, especially in event charts and world astrology, where it shows up often in charts of accidents and disasters. As planets move over time, a semi-square marks a stretch of minor crisis and irritation. It carries more weight inside a hard-rectangle pattern — two semi-squares and two sesquiquadrates bracketing an opposition. An exact semi-square can matter more than a wide-orb square. The usual orb is around 2°.

Historical Origin

The semi-square is attributed to the astronomer Johannes Kepler in the 17th century; it was not recognised by Ptolemy.

Definition

In Tradition

In Practice

Historical Origin

Further Reading