Kuṇḍalinī is a Sanskrit word that is fun to break down. One way of breaking it down is kuṇḍalin + ī. Kuṇḍalin means "snake" and "coiled, circular". When we speak of kuṇḍal earrings, they are the big hoop like earrings that you see some deities wearing in the Hindu iconographies. The root kuṇḍa means a "vessel, well, pit", and to break it down even further, kuṇḍ means "burning" and "agitating". The root li is an abbreviated form of liṅga, the divine masculine form of śiva that rises like a column out of the yoni śakti, divine feminine sexual energy.
Kuṇḍalinī is divine evolutionary energy, housed with each of us. It is matter (prakṛti), made up of three energies (guṇas) called sattva, rajas and tamas. At conception, the sattvic portion of it creates a central column of energy (suṣumna) that descends into the human vessel and coils itself, with the other two energies, three times at the base/pit of the spine cord. The rajasic and tamasic energies create the iḍā and piṅgalā channels, respectively, that rise up and cross through the suṣumna to create the 7 central energy plexuses in the body, the cakras.
Awakening this divine evolutionary energy is the path of the Karma Yogi. In fact, all of the yogas, Karma, Bhakti, and Jnana are required. However, the karmic "act" is this: to merge the śakti with the śiva, the inner divine feminine with the inner divine masculine, to create a union (yoga).
My Yoga lineage is a Kuṇḍalinī lineage. You can see it clearly represented in the iconography of the head of my lineage, Lakulīśa (pictured, from the Kayavarohan Shiva Temple). Note the kuṇḍal hoop earrings, the liṅga represented by a pillar of light behind the human form as well as by the erect phallus, the yoni as the base, and the serpent iconography to the left.
In Jyotisha, the Nakshatras of Āśleṣā, Pūrva Bhādrapadā, and Uttara Bhādrapadā all deal with the energy of Kuṇḍalinī and all three have the power to awaken it within themselves, if one chooses to go that route. Having more than one of these in a natal chart increases that chance.
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