Yantra is a Sanskrit word that means "circle of life" or (“instrument”).
The term yantra most usually refers to a symbolic
design, generally thought to impart magic or spiritual power on those who know
how to employ it in astrology (jyotisha) and tantra, a secret, ritually based
religious practice.
In other circumstances, such yantras are seen to represent
an aniconic form of a deity, like in the example of the Shriyantra or
Shrichakra, which is employed in rituals to worship the goddess Tripura Sundari.
In an astrological context, the yantras of the different
planets are utilized in rituals to modify their effects, mainly to control or
lessen the power of planets thought to be malefic or inauspicious.
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