A Glossary of Astrological Terms

Use this glossary to look up the meanings of words you come across on this website, or in your astrological reading. Just select the first letter of the word you need and click on it in the table below to go straight to that sector.

D

Debility

A planet is weakened when placed in a sign which is unsympathetic to its nature, such as Mercury, an airy planet, when placed in Sagittarius, a fiery sign.

Decan (Decanate)

A one-third (ten-degree) sector of a sign. Each sign has three decanates: 0-10 degrees, 11-20 degrees and 21-30 degrees. Each decan has its own ruler. Each decan is divided into two faces, a positive and a negative, each with its own ruler. Decanates themselves are also known as faces.

Decile

Minor aspect of 36°. Considered fortunate, also known as semi-quintile.

Declination

Distance of a planet north or south of the equator. Every part of the ecliptic has declination except the beginning of Aries and Libra, because the plane of the ecliptic is not parallel with that of the equator, which meet at those two points. The Sun has maximum declination of 23° 28', when it reaches the tropics of Cancer in the north and Capricorn in the south. Declination is due to the inclination of the earth in orbit. See Parallel.

Decreasing in Light

When a planet has passed the opposition to the Sun it is said to be decreasing in light and is correspondingly weaker. This especially applies to the Moon.

Decumbiture

A chart drawn for the time the patient falls ill, for the purpose of diagnosing illness.

Degree

The zodiac is divided into 360 equal degrees, which are themselves divided into twelve signs of thirty degrees each. One degree contains 60 minutes and each minute contains 60 seconds of longitudinal arc.

Descendant

The seventh house (or its cusp), governing marriage, partnership and open confrontation.

Descending

Planets appear to be descending between the tenth house cusp via the descendant and that of the fourth, when they begin to ascend. Descending planets are considered weaker than ascending ones.

Detriment

A planet is weaker and in its detriment when it is in the sign opposing that which it rules. For example, Mars is in detriment when placed in Libra, the opposite of Aries, or Taurus, the opposite of Scorpio.

Dexter

An aspect read to the right (ie separating from the point of aspect). See Sinister.

Dignities, Accidental and Essential

A planet is stronger when placed in certain sectors of the chart, which are called its dignities.

Accidental Dignity
A planet's position by house (angular, succedent, or cadent), or by other beneficial factors such as well-aspected, increasing in light, elevated, swift, etc.

Essential Dignity
This refers to a planet's position by sign (home sign, exaltation, or triplicity)

Accidental is more significant than Essential Dignity in the interpretation, although both are important. The unfortunate influence of a malefic is usually diminished when in dignity, whilst the fortunate influence of a benefic is increased. See Table of Planetary Values.

Direct Motion

In the normal order of the signs. The opposite of Retrograde Motion.

Directions

Aspects between planets in a progressed horoscope; also their aspects to the planets in the natal chart.

Dispositor

When a planet is in the sign ruled by another, that planet is said to be disposed of by the ruler, its dispositor. For example, Mars in Sagittarius in said to be disposed of by Jupiter, the ruler of that sign. Jupiter is thus the dispositor of Mars. Disposition by a benefic is favourable and especially so if the dispositor is elevated or more elevated than the disposed. Mutual Disposition (when planets are in each other's signs, eg: Moon in Leo and Sun in Cancer) is very favourable and reduces any surrounding negativity. Disposition is particularly important in Horary readings.

Diurnal

Planets above the horizon (between the first and seventh cusps via the Mid-Heaven), versus Nocturnal below the horizon.

Domal Dignity

A planet in its own sign.

Double-bodied Signs

Gemini is known as one of the double-bodied signs (dual signs) because it has two "bodies" in its symbol, the symbol of the Twins. The other dual signs are Sagittarius (part man, part beast) and Pisces (two fishes). They denote dual experiences, twins etc., when on the cusp of fifth or eleventh houses and especially on the ascendant or when populated by many planets. Dual or double-bodied signs often love variety and are drawn to be involved with two people at a time, or have two or more things happening at once, such as two jobs etc. See also Bi-corporal Signs

Dragon's Head

Caput Draconis, or Moon's North Node. The sign and degree occupied by the moon when crossing the ecliptic from south to north lattitude. It is usually considered somewhat benefic, and is the opposite of the Dragon's Tail (Cauda Draconis), the South Node, which is considered malefic. In Indian astrology, the Dragon's Head is called Rahu and the Dragon's Tail is called Ketu and both are considered malefic, though less so for ketu. These significant points traditionally have the strength of a planet and are especially important in directions.

Dragon's Tail

Cauda Draconis, or Moon's South Node. See Dragon's Head.

Dual Signs

Gemini; Sagittarius; Pisces. See Double-bodied Signs.

Dwadishamsha

Division in Indian Astrology of the zodiac into segments of two and a half degrees. Popularised in the West by Alan Leo.