radical : Having to do with the natal horoscope.

radical chart : The natal horoscope. In horary astrology, the term radical applies to a chart deemed readable by virtue of the Ascendant being greater than 3° and less than 27° in any sign.

radical position : The position a planet occupies in a natal horoscope.

radix : From the Latin, literally root. A natal horoscope.

rapport measurement : Literally related measurement; applied to progressions based on advancing a planet's natal position one degree for each year after birth.

reception : Shortened form of mutual reception.

rectification : The correcting of an inexact birthtime or the determining of an unknown birthtime through astrological methods.

refranation : The failure of an applying aspect to culminate, when the significator turns retrograde before reaching partile.

Regiomontanus : The German astrologer (fifteenth century) who devised the house system that bears his name. This system is based upon twelve equal divisions along Earth's equator projected upon the ecliptic.

relative houses : House three, seven, and eleven, ruled by air signs. Function is on human relationships. As a group, these houses form the Trinity of Association.

retrograde application : Term used in reference to a retrograde planet which, because of its retrograde motion, applies to an aspect with another planet. If both planets are moving toward each other, the term mutual application is used.

retrograde motion : The apparent backward motion of a planet when it appears, as observed from Earth, to reverse its travel direction relative to the zodiac.

revolution : One complete orbit or cycle. In a natal chart, a planet's return to its natal degree upon completing a circuit of the map.

right ascension : Measurement along the celestial equator eastward from 0° Aries that describes planetary positions in terms of degrees, minutes and seconds, not zodiacal signs. Sidereal time expressed in unit of arc.

rising planet : Any planet that is near the Ascendant in the natal horoscope. Rising planets will have a significant influence on the personality.

ruling planet : of the horoscope is that planet said to "rule" the Ascending sign. Likewise, planets rule the various houses in the chart based on the sign on the cusp of the respect houses. The planetary ruler of the signs are: Aries, Mars; Taurus and Libra, Venus; Gemini and Virgo, Mercury; Cancer, the Moon; Leo, the Sun; Scorpio, Pluto; Sagittarius, Jupiter; Capricorn, Saturn; Aquarius, Uranus; Pisces, Neptune.

ruminant signs : An obsolete term applied to signs symbolized by cud-chewing animals, namely, Aries (ram), Taurus (bull), and Capricorn (goat).

Sabian symbols : A system developed by Elsie Wheeler, Marc Edmund Jones and Dane Rudhyar that assigns an occult or esoteric meaning to each degree of the zodiac.

Saros cycle : The eighteen-year cycle, containing forty-one solar eclipses and twenty-nine lunar eclipses, in which an eclipse from each current Saros Series appears.

secondary progressions, secondary directions : The method of progressing a natal horoscope in which each day after birth is equated to a corresponding number of years after birth; commonly referred to as "day for a year" progressions.

See-Saw : The shaping arrangement in which, according to Marc Edmund Jones, the planets form tow distinct groups roughly opposite each other in a horoscope; symbolizing balance or the need to seek balance as a strong motivating factor.

semi-decile : The twentieth harmonic, 18°; interpreted as a weak minor easy aspect. Also called a vigintile.

semi-sextile : One of the influential minor easy aspects, the twelfth harmonic, 30°.

semi-square : The eighth harmonic, 45°; an important minor hard aspect in which planetary energies do not merge harmoniously but produce friction.

separating aspect : One in which the significator (faster moving planet of the two in aspect) is moving away from partile (the degree at which the aspect is exact).

septile : The seventh harmonic, 51 3/7°. A little-used minor aspect, probably inharmonious, thought to be associated with karma.

sesquiquadrate, sesqui-square : A multiple of the semi-square, and eighth harmonic aspect. A minor hard aspect, separating distance 135°, its influence is frictional.

sextile : The sixth harmonic, 60°; an major easy beneficial and opportune aspect.

shaping : Descriptive of the visual arrangement of planets in a horoscope. Marc Edmund Jones identified seven different patterns: the Bowl, Bucket, Bundle, Locomotive, See-Saw, Splash and Splay. Each shaping type is linked to specific astrological conditions and a particular interpretational focus. See individual listings. shaping is also referred to as planetary pictures and planetary patterns.

short ascension : Refers to the six signs that take less time than the other six to rise above the horizon, namely, Aries, Taurus, Gemini, Capricorn, Aquarius and Pisces; the spring and winter signs in the northern hemisphere.

sidereal astrology : An astrological system based on the constellations.

sidereal day : Twenty-four sidereal hours equal to 23 H, 56 M and 4 S of clock time.

sidereal time : Time measured in relation to the fixed stars. Astrological time data is listed in sidereal time units.

sidereal zodiac : Based on the division of the circle of twelve constellations: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces; the basis for sidereal astrology.

significator : The faster moving of two planets in aspect; the significator is said to aspect the slower moving planet (promittor). Also used in reference to the planetary ruler of a house, matter, object or person. See also promittor.

singleton : Planet that is the sole occupant of the horoscope hemisphere in which it is placed; gives balance to a horoscope with nine planets in the other hemisphere.

signs : The twelve divisions of the zodiac: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, sagittarius, Capricorn, Aquarius and Pisces.

sinister aspect : Sinister (Latin); term replaced with departing aspect, which refers to aspects in which the direction from significator to promittor is backward in the zodiac, clockwise in a horoscope. See also departing aspect.

slow of course : Term used to describe a planet's motion when its rate of travel is less than its mean daily motion.

solar : From the Latin sol, the Sun; refers to the Sun.

solar chart : A horoscope set up with the placement of the Sun positioned at the Ascendant. This type of chart is sometimes used with the hour of birth is not known.

solar arc : The distance the Sun travels from birth position to its secondary progressed position. A system of progressions adds the soar arc at a given year to the natal positions of house cusps and/or planets. A similar method based on the mean solar arc multiplies 59'08" (Naibod arc, Sun's mean daily motion) by the individual's age in years to determine the proper increment to add to natal positions.

solar return, solar revolution : A horoscope erected for the exact time in a given year when the transiting Sun reaches the same position it held in the natal horoscope; used to project conditions for the year of interest.

solstice : Either of two points on the ecliptic at which the Sun reaches it farthest point north (0° Cancer) or south (0° Capricorn) of the equator. The longest day of the year occurs at summer solstice as the Sun moves at its slowest rate; the winter solstice marks the shortest day of the year as the Sun reaches its fastest rate.

Splash : A planetary arrangement described by Marc Edmund Jones in which the planets are fairly evenly distributed around the horoscope. This dispersion of planets suggests dispersion of interests.

Splay : A planetary arrangement identified by lack of symmetry and irregularly spaced planets and groups of planets as described by Marc Edmund Jones; symbolic of individualism and nonconformity.

square Fourth harmonic, 90° : A major hard aspect, the square generates tension and stirs action. Also called a quadrate, quartile or tetragon.

station : A planet is said to "make a station" at the degree it occupies when it appears motionless as its direction changes from direct to retrograde or vise versa.

stationary, stationary motion : Term used to describe apparent lack of motion when a planet's direction of travel changes from direct (forward in the zodiac) to retrograde (backward in the zodiac) or vice versa. Planetary energy, focused at the stationary position, is considered strong in a horoscope when a planet is stationary.

stellium : A multiple conjunction that occurs within one sign or house, indicating a focal point of energy or interest. Also called a satellitium. the term may include multiple conjunctions that occupy more than one sign. See also multiple conjunction.

succedent houses : From the Latin succedere, to follow; houses two, five, eight and eleven, which follow the angular houses. Also called the fixed houses, being ruled naturally by the fixed signs: Taurus, Leo, Scorpio and Aquarius. The mode of action associated with these houses reflects fixed qualities of steadiness and reliability.

superior planets : Planets whose orbits are larger than Earth's. The term is sometimes restricted to the three outermost planets: Uranus, Neptune and Pluto.

swift in motion : Said of a planet whose rate of travel is greater than its mean daily motion.

synastry : The astrological technique of comparing natal horoscopes to gain insight into the strengths and weaknesses inherent in the relationship that exists between the individuals involved. See also composite chart.

synthesis : The art of combining the various factors revealed in a horoscope and building a balanced judgment of the chart as a whole.

syzygy : From the Latin, yoked together; refers to points at which a planet conjuncts or opposes the Sun; usually used in reference to those Sun/Moon conjunctions and oppositions that are eclipse events.