Yantra

Yantra (यन्त्र) is the Sanskrit word for a mystical diagram, especially diagrams from the Tantric traditions of the Indian religions. They are used for worship of deities in temples or at home; as an aid in meditation; used for the benefits given by their supposed occult powers based on Hindu astrology and tantric texts.

In Classical Sanskrit, the generic meaning of yantra is "instrument, contrivance, apparatus". In Rigvedic Sanskrit, it meant an instrument for restaining or fastening, a prop, support or barrier, etymologically from the root yam "to sustain, support" and the -tra suffix expressing instruments. The literal meaning is still evident in the medical terminology of Sushruta, where the term refers to blunt surgical instruments such as tweezers or a vice. The meaning of "mystical or occult diagram" arises in the medieval period (Kathasaritsagara, Pancharatra).

Madhu Khanna in linking mantra, yantra, deva, and thought forms states:

Mantras, the Sanskrit syllables inscribed on yantras, are essentially "thought forms" representing divinities or cosmic powers, which exert their influence by means of sound-vibrations.

Yantras are usually associated with a particular deity and are used for specific benefits, such as: for meditation; protection from harmful influences; development of particular powers; attraction of wealth or success, etc. They are often used in daily ritual worship at home or in temples, and sometimes worn as a talisman.

As an aid to meditation, yantras represent the deity that is the object of meditation. These yantras emanate from the central point, the bindu. The yantra typically has several geometric shapes radiating concentrically from the center, including triangles, circles, hexagons, octagons, and symbolic lotus petals. The outside often includes a square representing the four cardinal directions, with doors to each of them. A popular form is the Sri Chakra, or Sri Yantra, which represents the goddess in her form as Tripura Sundari. Sri Chakra also includes a representation of Shiva, and is designed to show the totality of creation and existence, along with the user's own unity with the cosmos.

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