Day House. v. Ruler.
Day of Week, to determine v. Dominical Letter.
Daylight Saving Time. v. Time, Daylight-saving.
Day Triplicity. Older authorities deemed that in the daytime some planets are stronger when
posited in Signs of a certain element; i.e. Saturn in an Air-Sign, the Sun in a Fire Sign, Mars in a
Water Sign, and Venus in an Earth Sign.
Debility. An embracive term, preferably applied to any planet disadvantageously placed by
virtue of its House position, but frequently employed loosely as a synonym of Detriment.
Decade. Ten consecutive years; any grouping of ten.
Decanate, Decan. A term applied to a subdivision of Sign into 10° arcs, referred to as the
first, second and third decanates or decans. The interpretation of Decans is based upon a
system of rulerships, of which there are two in common use. One method ascribed Mars to
the first Decan of Aries and thence carried a fixed series throughout the 36 Decans, ending
again with Mars ruling the third Decan of Pisces. The series is Mars, Sun, Venus, Mercury,
Moon, Saturn, Jupiter; as follows:
..............First Decan..Second Decan..Third Decan
...Aries........ Mars ........ Sun ....... Venus
...Taurus....... Mercury ..... Moon ...... Saturn
...Gemini....... Jupiter ..... Mars ...... Sun
...Cancer....... Venus ....... Mercury ... Moon
...Leo.......... Saturn ...... Jupiter ... Mars
...Virgo........ Sun ......... Venus ..... Mercury
...Libra........ Moon ........ Saturn .... Jupiter
...Scorpio...... Mars ........ Sun ....... Venus
...Sagittarius.. Mercury ..... Moon ...... Saturn