ketu

 The Sanskrit word "Ketu" primarily means a "banner" 

or "flag" and also refers to comets, meteors, the 

descending lunar node, and a spiritual symbol of 

otherworldly knowledge and detachment.

Linguistic Meaning

In Sanskrit, Ketu (केतु) has multiple literal meanings: it represents 

a banner, flag, or sign, a chief or eminent person, brightness 

or clear light, and an unusual or striking phenomenon such 

as a comet or meteor 

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. It is derived from 

the Proto-Indo-European root keyt- meaning "shine" or "glow" 

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. 

During Vedic times, it was also used to denote daytime 

or rays of light

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 .

Mythological and Astrological Significance

Ketu is one of the Navagraha (nine planetary deities) in Hindu 

astrology, representing the descending (south) lunar node. In 

mythological accounts, Ketu is the body of the Asura Svarbhanu, 

whose head became Rahu when severed by the god Vishnu during 

the churning of the ocean to obtain amṛta (nectar of immortality) 

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. 

Astronomically, Ketu does not correspond to a physical planet 

but is considered a shadow planet that influences eclipses and 

signifies the intersection of the Sun's and Moon's paths 

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Astrologically, Ketu is seen as both malefic and benefic, associated 

with spiritual growth, detachment, insight, psychic abilities, and 

liberation (moksha). It often symbolizes loss or sorrow to promote 

spiritual development, turning the individual toward God 

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. 

Ketu is associated with the Nakshatras (lunar mansions) Ashvini, 

Magha, and Mula

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 , and in iconography, is depicted either 

as a torso without a head, riding a vulture, and carrying symbols 

like a spear or snake-noose 

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Symbolic and Cultural Usage

Beyond astronomy and astrology, "Ketu" can refer to shooting stars 

or meteors, used metaphorically as a banner or sign in rituals and 

literature 

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. In Buddhism, Ketu is sometimes 

interpreted as a spiritual guide or enlightened being, reflecting 

the process of refinement from material concerns to spiritual 

awareness 

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In summary, Ketu encompasses the notions of light, signs, celestial 

phenomena, and spiritual transcendence, linking the material 

world to higher spiritual insight while maintaining roots in Sanskrit 

language and Indian mythology 

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