Decan

Definition

A decan is the division of each zodiac sign into three equal stretches of ten degrees. Every sign thereby has three decans that nuance the expression of the sign according to the planet's inner position. Classical astrology assigns each decan a secondary ruler, which refines further the reading of a planet or angle according to the exact stretch of the sign in which it is placed within the chart.

In context

Where a Sun sits at 5 degrees of Aries, it falls into the first decan of the sign, associated with the principal ruler: Mars; at 15 degrees, into the second decan, with secondary ruler the Sun; at 25 degrees, into the third, with ruler Jupiter. The decan does not change the planet's membership in the sign, but it shifts its accent. It is a fine tool for distinguishing two people sharing the same solar sign yet carrying different internal accents.

To go deeper

The decan belongs to the classical subdivisions of a sign:

• Ruler: principal planet governing a sign.
• Triplicity: three signs of one element.
• Terms: another classical subdivision, finer than the decan.