Sinister
Definition
Sinister is a classical astrological term describing the direction in which one planet casts an aspect to another. Derived from the Latin word for “left,” it usually refers to an aspect projected forward through the zodiacal order. For example, a planet in Aries casts a sinister trine toward Leo. In this technical context, sinister does not mean evil, dangerous, or unfortunate.
Astrological Meaning
Traditional astrologers distinguished sinister aspects from dexter aspects, which are cast backward against the zodiacal order. The distinction identifies which planet is actively casting the aspect and can help clarify the relationship between the two bodies. Some classical authorities considered dexter aspects more forceful because their direction opposed the daily apparent motion of the heavens, but interpretation varies by period and astrological school. The aspect itself—such as a square, trine, or sextile—still provides the primary meaning.
Why It Matters
Recognizing a sinister aspect adds directional detail to natal, horary, electional, and mundane chart interpretation. It can show how one planet reaches toward another rather than treating every aspect as perfectly interchangeable. This distinction is especially useful when studying traditional methods involving planetary testimony, reception, and relative influence. It should be weighed alongside sign placement, planetary condition, house rulership, reception, and whether the aspect is applying or separating.
Related Encyclopedia Entries
- Traditional Astrology
- Astrological Terminology
- Natal Chart
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