In astrology, a planet distant from another one-third of the circle is said to be in trine; one-fourth, it is in square; one-sixth or two signs, it is in sextile; but when one-half distant, it is said to be “opposite.”
In sextile, square, and trine, and opposite Of noxious efficacy.
N.B. Planets distant from each other six signs or half a circle have opposite influences, and are therefore opposed to each other.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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