Radix refers to the natal, root or base chart.
The Rational Horizon is the Geocentric Horizon (a Great Circle parallel to the apparent horizon but passing through the centre of the Earth) projected onto the celestial sphere.
Rationalised Semi-Arc is a co-ordinate system which assigns 0 to 90 degrees to the diurnal semi-arc Ascendant to MC, 90 - 180 degrees to the diurnal semi-arc MC to Descendant, 180 - 270 to the nocturnal semi-arc Descendant to IC, and 270 - 360 degrees to the nocturnal semi-arc IC to Ascendant.
Relocation is a popular method of Relocating the Natal Chart to a different locality, usually the current place of residence, or a proposed destination, such as a holiday location. In the relocated chart the angles and house cusps are recalculated to reflect the new place but the planet positions will remain unaffected. The new chart can then be analysed giving an indication of how the person relates to the new environment.
A planet is said to retrograde when it appears to be travelling backwards through the zodiac. Opinions vary on the interpretation of retrogradation. In natal work, it is considered an affliction, in horary work, it indicates that there is a need to go back over the matter and review it and in predictive work, it is often associated with the need to hold off taking important steps. All of the planets will be retrograde at some point in an 18 month period. The Sun and the Moon are never retrograde.
Planet: Planet 1 returns to same longitude as Natal.
Midpoint: Transiting midpoint of Planet 1 and Planet 2 returns to same longitude as Natal.
Phase angle: Tr planet 1 and Tr Planet 2 return to same phase angle as Natal.
Kinetic Solar: Transiting Sun returns to same longitude as Progressed Sun.
Kinetic Lunar: Transiting Moon returns to same longitude as Progressed Moon.
Synodic: Transiting Sun/Moon angle at same angle as Natal Sun/Moon. The synodic
cycle is the month of about 29.5 days of the lunar phases.
Metonic: Transiting Sun/Moon angle at same angle as natal Sun and Moon, in zodiacal positions almost same as natal positions. The metonic cycle is almost exactly 19 years.
Anlunar: Transiting Moon returns to position of Moon at the most recent solar return.
Right Ascension (RA) is the angular distance measured from the vernal point in an eastern direction along the celestial equator. RA can be expressed in degrees and minutes of arc, or in hours and minutes of sidereal time.