in astrology, is applied to the planets when in their detriment, as astrologers speak, i.e. when they have lost their force or influence, as is pretended, by reason of their being in opposition to some others which check and counteract them. Or it is used when a planet is in a sign opposite to that in which it has its greatest effect or influence, which is called its exaltation. Thus, the sign Aries being the exaltation of the sun, the opposite sign Libra is its dejection.