Kaivalya (from SANSKRIT kevala, sole or only) liter-ally means “isolation” and refers to the liberated state of the self, when it is “isolated” completely from the pulls and distortions of PRAKRITI, or natural reality. The term originated in the ancient SAMKHYA tradition and is important in the yoga tradition of PATANJALI. Both living and dead per-sons may be in the state of kaivalya. It is a unique state where one becomes absorbed in the root-consciousness of the Self (purusha) alone. Bliss is not an element of traditional kaivalya.
Further reading: M. N. Parthasarathi, Journey to Alone-ness: Commentaries on the Kaivalya Upanishad (Mumbai: Eeshwar, 2001); Ian Whicher, The Integrity of the Yoga Darsana: A Reconsideration of Classical Yoga (Albany: State University of New York Press, 1998).
Encyclopedia of Hinduism. A. Jones and James D. Ryan. 2007.