Ekajaṭī or Ekajaṭā, (Sanskrit: "One Woman"; Wylie: ral gcig ma: one who has one knot of hair), also known as Māhacīnatārā, she is one of the 21 Taras. Ekajati is, along with Palden Lhamo deity, one of the most powerful and fierce goddesses of Vajrayana Buddhist mythology. According to Tibetan legends, her right eye was pierced by the tantric master Padmasambhava so that she could much more effectively help him subjugate Tibetan demons.
Ekajati is also known as "Blue Tara", Vajra Tara or "Ugra Tara". She is generally considered one of the three principal protectors of the Nyingma school along with Rāhula and Vajrasādhu (Wylie: rdo rje legs pa).
Often Ekajati appears as liberator in the mandala of the Green Tara. Along with that her ascribed powers are removing the fear of enemies, spreading joy and removing personal hindrances on the path to enlightenment.
Ekajati is the protector of secret mantras and "as the mother of the mothers of all the Buddhas," represents ultimate unity. As such her own mantra is also secret. She is the most important protector of the Vajrayana teachings, especially the Inner Tantras and termas. As the protector of mantra, she supports the practitioner in deciphering symbolic dakini codes and properly determines appropriate times and circumstances for revealing tantric teachings. Because she completely realizes the texts and mantras under her care, she reminds the practitioner of their preciousness and secrecy.Düsum Khyenpa, 1st Karmapa Lama meditated upon her in early childhood.
According to Namkhai Norbu, Ekajati is the principal guardian of the Dzogchen teachings and is "a personification of the essentially non-dual nature of primordial energy."