KĀLACAKRA ("Wheel of Time"; Tib., dus kyi 'khor lo; Mong., čay-un kürdü) is the Sanskrit name for the principal male deity and personification of the Kālacakra Tantra, an Indian Buddhist esoteric treatise belonging to the class of unexcelled yoga-tantras (anuttarayoga-tantra). In this Tantric tradition, the deity Kālacakra represents spiritual knowledge (vidyā) and the state of immutable bliss, which is attainable only through the yogic practices that are specific to the Kālacakra tradition. Kālacakra is a single, unified reality, which is given different names in the Kālacakra tradition: Ādibuddha (Primordial Buddha), sahajakāya (innate body), jñānakāya (gnosis body), viśuddhakāya (pure body), vajrayoga (indestructible union), and the like. This nondual reality has two main aspects: the phenomenal world of multiplicity (saṃsāra) and the unitary ultimate reality (nirvāṇa).

The Kālacakra tradition is...