Hypogeon

Definition

Hypogeon is a classical astrological term for the lower meridian point beneath the Earth, usually identified with the Imum Coeli, or IC. Its name means “under the Earth.” It stands opposite the Midheaven and forms one of the chart’s four principal angles. Depending on the house system, the exact Hypogeon may fall within the fourth house rather than marking its cusp, so it is not always synonymous with the entire fourth house.

Astrological Meaning

Traditionally, the Hypogeon represents foundations, ancestry, home, land, family origins, and matters that remain private or concealed. It can also describe the roots from which a person’s public life develops. Planets close to this angle are considered angular and potentially influential, although their expression may be more inward, domestic, or personal than publicly visible. Interpretation depends on the sign at the Hypogeon, its planetary ruler, nearby planets, and their condition in the natal chart.

Why It Matters

The Hypogeon helps an astrologer examine the chart’s deepest supporting structures rather than focusing only on outward achievement. Its axis with the Midheaven can clarify the relationship between private foundations and public direction. Careful attention to the exact degree is especially important when comparing house systems or assessing whether a planet is truly angular.

Related Encyclopedia Entries

• Traditional Astrology
• Astrological Terminology
• Natal Chart
• Imum Coeli
• Midheaven
• Angular Houses