In astrology, a planet's domicile is the zodiacal sign over which it has rulership. This is a separate concept from the houses of the horoscope. A planetary ruler is given to each sign, over which the planet is said to have a more powerful influence when positioned therein. The ruling planet associated with a sign is also used as an implied focus of interpretation for the signs on house cusps in a chart. A planet is considered to be in domal dignity when it is positioned in the sign it rules. This is the strongest of the five essential dignities of a planet. Domicile is an archaic term in infrequent, specialist uses today; most astrologers use the simpler term "sign".

Most horoscopic traditions of astrology systems divide the horoscope into a number of houses whose positions depend on time and location rather than on date. In Hindu astrological tradition these are known as Bhāvas. The houses of the horoscope represent different fields of experience wherein the energies of the signs and planets operate—described in terms of physical surroundings as well as personal life experiences.