Glossary and pronunciation guide

The Good Daemon, the Greek name for the eleventh place, and one of the six Ptolemy names directly.

Eleventh House

also written agathos daimōn

A printed yearly compilation of calendar, astronomical and often astrological matter. The main vehicle by which astrology reached ordinary readers before the newspaper column.

The Sun-Sign Column

Height above the horizon in degrees, from 0 at the horizon to 90 at the zenith. Unlike declination it depends on where and when you are standing.

The four points where the great circles of the local sky meet the ecliptic: ascendant, midheaven, descendant and imum coeli. The only chart features that depend on the minute of birth.

The angles

The three-way classification of houses by their relation to the angles: houses 1, 4, 7 and 10 are angular, the ones following them succedent, the ones falling away cadent.

First House

also written succedent, cadent

The exact degree of the ecliptic rising on the eastern horizon at the moment and place of birth. Not the same thing as a rising sign, which is only the sign that degree happens to fall in.

The angles

also written rising

A named angular distance between two bodies measured in ecliptic longitude. Five were used in the Hellenistic material; modern practice adds more.

Aspects

A recognised figure of stars that is not one of the official constellations, or is only part of one. The Plough within Ursa Major is the usual English example.

The relation between two signs that share no aspect at all, being one, five, seven or eleven signs apart. In the Hellenistic material this is a stated relation, not merely an absence.

Aspects

The offset, in degrees, between the tropical and sidereal zodiacs. There is no single agreed value: this site offers five, names which one is in force, and refuses to pick.

Three Reference Frames

also written ayanāṃśa

An unequal subdivision of a sign, five per sign, each assigned to a planet. "Term" is the older English word for the same thing. The degree widths differ between witnesses.

Essential Dignity

also written term, bounds, terms

Two bodies at the same ecliptic longitude, zero degrees apart.

Aspects

A region of sky, not a group of stars. Since 1930 the boundaries are fixed rectangles in right ascension and declination, so every point of sky is in exactly one.

Three Reference Frames

A date falling roughly midway between a solstice and an equinox. Four are usually named, and how old the four-fold scheme is turns out to be a much harder question than it looks.

Cross-Quarter Days

also written cross-quarter

The moment a body crosses the meridian and reaches its greatest altitude for that day.

The boundary between one house and the next. Under whole sign houses a cusp is a sign boundary; under the other six it is a computed degree that usually falls mid-sign.

House Division

Latvian traditional four-line songs, collected in the nineteenth century in enormous numbers. The largest body of evidence for Baltic seasonal practice, and the hardest to date.

The Latvian Dainas as Evidence

Latitude measured from the celestial equator. Together with right ascension it fixes a point on the sky independently of any observer's horizon.

The degree setting on the western horizon, exactly opposite the ascendant.

The angles

The sign opposite a planet's domicile, in which it is held to be weakened. Derived from the rulership scheme rather than attested separately.

Essential Dignity

The practice of seeking knowledge of hidden or future things by a technique. Used on this site as a neutral description of what a practice was for, never as a verdict on whether it worked.

The sign a planet is said to rule. The oldest and least disputed of the five dignities.

Essential Dignity

also written rulership

The circle the Sun appears to trace against the stars over a year, which is really the plane of Earth's orbit seen from inside it. Every zodiac, tropical or sidereal, divides this one circle.

Three Reference Frames

A table, or now a program, giving the computed positions of the bodies over time. This site computes its own in the reader's browser and transmits nothing.

A date chosen as the fixed reference for a coordinate system, because precession keeps moving the alternative. J2000 means noon on 1 January 2000, and is the epoch this site's sky uses.

also written J2000

Either of the two moments a year when the Sun crosses the celestial equator. The March one defines 0 degrees Aries in the tropical zodiac.

Solstices and Equinoxes

The family of schemes rating a planet by the zodiacal degree it occupies rather than by its position in the sky. Five of them, and the tables disagree between witnesses.

Essential Dignity

A sign, and in some schemes a single degree, in which a planet is held to be strengthened. The scheme is Babylonian in origin and its degrees vary between sources.

Essential Dignity

A ten-degree third of a sign, three per sign, each assigned to a planet. Egyptian in origin, where the same divisions were a timekeeping scheme rather than a dignity.

Essential Dignity

also written decan

The sign opposite a planet's exaltation.

Essential Dignity

The first morning a star or planet is visible again in twilight after a spell lost in the Sun's glare. The oldest calendar events on this site are of this kind.

Heliacal Risings

The circle dividing the sky you can see from the sky beneath your feet. It depends entirely on where you are standing, which is why a birthplace is needed and not only a birth time.

In the ancient technical sense, the ascendant itself: the degree that was rising. The modern sense, a whole chart or a newspaper column, is a later widening of the word.

First House

One of twelve divisions of the chart reckoned from the ascendant. Seven systems divide seven different objects into twelve and disagree by tens of degrees.

House Division

also written places

The lowest point, opposite the midheaven and underfoot. Dorotheus calls the same place the cardine of the earth.

English usage is split. "EYE-mum SEE-lye" follows the older English convention for Latin and is what many British practitioners say; the respelling given here follows the church Latin most modern speakers have heard. This site does not treat either as correct.

The angles

also written imum coeli

The insertion of an extra day, week or month to keep a calendar aligned with the season it claims to track.

Bede and the Old English Months

The Sanskrit term for the science of the heavenly bodies, covering what English separates into astronomy and astrology. Not a synonym for the phrase "Vedic astrology".

"Vedic Astrology": the Term

also written jyotiṣa

The Evil Daemon, the Greek name for the twelfth place. Ptolemy names it in order to exclude it from his technique.

Twelfth House

also written kakos daimōn

A calendar whose months follow the Moon and whose years are kept in step with the Sun by inserting a thirteenth month from time to time.

The Chinese Lunisolar Calendar

The circle running from due north through the zenith to due south. A body is at its highest as it crosses it, which is what culmination means.

The Greek word for the midheaven, literally the mid-heaven. Ptolemy uses it more than any other place-name.

Tenth House

also written mesouranēma

The degree of the ecliptic crossing the meridian, the highest point the ecliptic reaches at that moment. Ptolemy's most-used place-name after the ascendant.

The angles

also written mid-heaven, mesouranēma

A chart cast for a birth, and by extension the branch of the subject that reads one.

also written natal

Either of the two points where the Moon's orbit crosses the ecliptic. Eclipses happen when a new or full Moon falls near one.

The angle between the ecliptic and the celestial equator, currently about 23.4 degrees. It is what makes seasons, and four of the seven house systems need its value for the date.

Two bodies 180 degrees apart, on opposite sides of the chart.

Aspects

The tolerance allowed around an exact aspect, so that a trine two degrees from exact still counts. How wide an orb should be has never been agreed.

Aspects

Said of a planet holding none of the five essential dignities in the degree it occupies. The scoring that turns this into a number is Lilly's, and is not ancient.

William Lilly

also written peregrination

The slow wobble of Earth's axis that moves the equinox point westward against the stars, about one degree every seventy-two years. It is why the two zodiacs came apart.

Precession of the Equinoxes

Ptolemy's length-of-life technique, which starts from one of a short list of eligible places and follows it forward. His house vocabulary is largely the vocabulary of this one procedure.

Claudius Ptolemy

also written prorogative

The apparent backward motion of a planet against the stars, produced by Earth overtaking it or being overtaken. Nothing reverses; the geometry of the sightline does.

Longitude measured around the celestial equator rather than the ecliptic, in hours rather than degrees. Two of the seven house systems divide this circle instead of the ecliptic.

also written right ascension

The division of the planets, and of charts, into diurnal and nocturnal according to whether the Sun was above the horizon. It organises the whole of Dorotheus.

Sect

Two bodies 60 degrees apart, a sixth of the circle.

Aspects

The zodiac anchored to the stars rather than to the equinox. Several conventions exist for where exactly to anchor it, and they disagree by about a degree.

Three Reference Frames

Either of the two moments a year when the Sun reaches its greatest distance from the celestial equator, and its daily northward or southward drift stops.

Solstices and Equinoxes

Two bodies 90 degrees apart, a quarter of the circle.

Aspects

The moment a planet's apparent motion stops before reversing, at the start or end of a retrograde stretch.

The time between successive same alignments of a body with the Sun as seen from Earth, as against the sidereal period, which is one orbit against the stars. The two differ.

Two bodies 120 degrees apart, a third of the circle.

Aspects

The rulers assigned to each group of three signs, usually differing by day and night. The water triplicity is where Lilly and the Greek sources part company.

Essential Dignity

The zodiac anchored to the equinox: 0 degrees Aries is defined as the March equinox point, wherever the stars have drifted to. This site's default.

Three Reference Frames

The house system in which the sign containing the ascendant is the whole first house and the following signs are the following houses. The oldest attested system, and this site's default.

House Division

also written whole sign

The point directly overhead. Its opposite, directly underfoot, is the nadir.

An astronomical handbook with tables, the standard working reference of Islamicate astronomy. Dozens survive, and they are how Indian and Greek methods reached one another.

The Zīj al-Sindhind

also written zij, zīj

A division of the ecliptic into twelve. Which twelve depends on where the division is anchored, which is the whole of the difference between the tropical and sidereal conventions.

Three Reference Frames