A Mansion or House appears to be that sign in which the planet is peculiarly at home for some reason or other.
The Exaltation or Honour is that degree of a sign in which the planet named has its greatest power; but the degree was often neglected, and Aries was called the Exaltation of the Sun, simply.
The Fall (Lat. occasus vel detrimentum) of a planet is the sign opposite its mansion. Libra is opposite Aries; therefore Libra is the Fall of Mars.
The Dejection or Depression (Lat. dedecus) of a planet is the sign opposite to that of its exaltation. Libra is opposite Aries; therefore Libra is the Dejection of the Sun. And so on.
A Triplicity is a combination of three signs in the form of a triangle, each 120° apart. Thus Aries, Leo, and Sagittarius form the first triplicity; Taurus, Virgo, Capricorn, the second; Gemini, Libra, Aquarius, the third; Cancer, Scorpio, Pisces, the fourth. Equal divisions of a sign (third-parts, namely) are called Faces. There were also unequal divisions called Terms.
The 'mobill' or movable signs are Aries, Cancer, Libra, Capricorn. The 'fixe' or fixed signs are Taurus, Leo, Scorpio, Aquarius. The 'common' signs are Gemini, Virgo, Sagittarius, Pisces.
The signs Aries, Gemini, Leo, &c. (taking every other sign) are diurnal or masculine. The rest, Taurus, Cancer, &c., are nocturnal or feminine.
The first six signs, Aries to Virgo, are northern or sinister signs. So called because astrologers looked towards the east or ascendent.
The last six, Libra to Pisces, are southern or dexter signs.
The signs Cancer to Sagittarius are western, sovereign, right, or direct signs. Cf. Astrol. ii. 28, and see [Fig. 2].