Astrology Dictionary - I

Astrology Dictionary - I


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Age of Aquarius • Air • Angles • Applying • Aquarius • Archetype • Aries • Arrowhead • Ascendant • Aspect • Aspect Configuration

Birth Chart • Boomerang

Cancer • Capricorn • Cardinal • Cazimi • Celestial Equator • Centaurs • Chart • Chiron • Collection of Light • Collective • Collective Unconscious • Combust • Conjunction, Conjuct, Conjoin • Contra-Parallel • Cradle configuration • Cusp

Declination • Descendant • Direct • Dispositor • Dissociate Aspect

Earth (element) • Earth (planet) • Eclipse • Eclipse times • Ecliptic • Element • Equinox

Final Dispositor • Fire • Fixed • Full Moon

Gemini • God's Fist • Grand Cross • Grand Sextile • Grand Square • Grand Trine

Hard Wedge • Houses • Houses (meanings)

IC, Imum Coeli • Inconjunct • Intercepted Planet • Intercepted Sign


Kite • Grand Trine Kite • Yod Kite

Leo • Libra • Lights, Luminaries • Lunar Eclipse • Lunar Nodes

Major Aspects • Mars • MC, Medium Coeli • Mean Lunar Node • Mercury • Mercury Retrograde • Midheaven • Modalities • Moon • Moon's Nodes • Multiple Conjunction • Mutable • Mutual Reception • Mystic Rectangle

Nadir • Natal Chart • Neptune • New Moon • North Node

Octile • Opposition • Orb • Out of Bounds • Out of Sign Aspect

Parallel • Part of Fortune, Pars Fortuna • Pisces • Planet • Pluto • Points • Precessed Solar Return • Precession of the Equinoxes • Progressions • Ptolemaic Aspects

Quadriform • Quincunx

Retrograde • Rising Sign • Rolling Conjunction • Rosetta • Ruler • Rulerships

Sabian Symbols • Sagittarius • Saturn • Scorpio • Semi-Sextile • Semi-Square • Separating • Sesqui-Quadrate • Sesqui-Square • Sextile • Shadow (planetary) • Shadow (psychological)
• Sidereal Zodiac • Sign • Solar Eclipse • Solar Return • Solstice • South Node • Square • Station(ary) • Stellium • Sun

Taurus • Thor's Hammer • Traditional Rulerships • Transits • Transpersonal Planets • Trapeze • Trine • Tri-Octile • Tropical Zodiac • True Lunar Node • True vs Mean Nodes • T-Square, T-Cross


Venus • Virgo

Water • Waxing, Waning • Wedge


Zenith • Zodiac



Imum Coeli

The lowest point in the sky (nadir) that a planet can travel relative to the horizon. If you are born at midnight, the Sun would be found around the IC of the chart. "IC" stands for the Latin Imum Coeli which means "bottom of the heavens." The IC also forms the cusp (starting point) of the 4th House of ancestral roots, family (especially your family-of-origin), home and the foundation of your life. Associated with one of the parents, often the father. The sign on the IC of the chart, and planets found in the 4th House, indicate the experiences of your childhood home, family, ancestry and what is important to you in the home you make in adulthood. Pronounced: Eye-SEE. Compare Midheaven.Top of Page I.C. or Imum Coeli - one of the Angles

I.C. or Imum Coeli (Lower Heaven)


A term referring to both the Quincunx and Semi-Sextile aspects.

Pronounced: IN-con-junct. Top of Page


Intercepted Planet

When a planet is positioned in a sign that is intercepted in a natal chart, that planet is said to be intercepted. The energy of this planet tends to be more difficult to bring out directly in the person's life. Since the intercepted sign requires the mastery of the preceding sign (on the cusp of its house), this usually takes time. Therefore, it is common that this planet's energy doesn't "bloom" until later in life. There tends to be a "deeper issue" about that planet's energy in the person's life. See: Intercepted Sign. Top of Page Diagram showing example of an Intercepted Planet

Intercepted Planet (shown in white house)

Intercepted Sign

This is a characteristic of how a zodiac sign is sometimes positioned in a

natal chart. Each natal house cusp (the beginning of that house) is positioned within a sign, and usually each house cusp lands in a different sign — 12 signs, 12 house cusps.

But sometimes a house is so large that it completely encompasses a sign. The encompassed sign is said to be intercepted in that house. This tends to happen more often in very northern or southern latitudes, and is a distortion effect of the extreme latitudes, although it can occur near the equator too.

This interception effect also only happens with certain house systems, which have variable sized houses. Equal house system does not have this distortion, since the houses are always 30 degrees in length.

Intercepted signs always happen in pairs. Opposite houses always form an axis, as do opposite signs. So when a sign is intercepted, its opposite sign is also intercepted in the opposite house.

An intercepted sign can be thought of like "a room within a room," where the surrounding house is the outside room and the intercepted sign is contained within it. (I believe I first heard this analogy in Joanne Wickenburg's wonderful book, Journey Through the Birth Chart.)

In order to access the inner sign, the person must "go through" the sign on the cusp of that house (usually the preceding sign). The person first needs to master the qualities and circumstances of the sign on that cusp, and only then can the person begin to fully access the inner sign within that house and any planets contained within that sign. See: Intercepted Planet. Top of Page

Diagram showing an example axis of Intercepted Signs

Intercepted Sign Axis (shown in white houses)

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