Placidus Houses

Definition

Placidus Houses is a quadrant house system used to divide an astrological chart into twelve areas. It anchors the chart to the Ascendant–Descendant and Midheaven–IC axes, then calculates intermediate cusps from divisions of a point’s apparent daily motion. The resulting houses are often unequal in size, and calculations can become impractical at extreme latitudes.

Astrological Meaning

In interpretation, each Placidus house represents a field of experience, such as identity, relationships, vocation, or shared resources. A planet’s house describes where its symbolism may become especially noticeable, while its sign describes how it tends to operate. Because house systems calculate cusps differently, a planet near a boundary may change houses when another system is used. Placidus charts can also contain intercepted signs, which fall entirely within a house without appearing on a cusp.

Why It Matters

Placidus is widely used in modern natal and predictive astrology, so understanding it helps when reading charts, software reports, and transit interpretations. During a transit, the moving planet is considered separately from the natal house structure it crosses. Comparing Placidus with another house system can reveal which themes remain consistent and which depend on calculation method, encouraging a more thoughtful reading rather than a fixed conclusion.

Related Encyclopedia Entries

• Natal Chart
• Astrology Techniques
• Predictive Astrology