The Dharmakāya (lit. Truth Body or Reality Body) is a central concept in Mahayana Buddhism forming part of the Trikaya doctrine that was first expounded in the Saddharma Pundarika Sutra (The Lotus Sutra), composed in the first century BCE. It constitutes the unmanifested, 'inconceivable' (Sanskrit: acintya) aspect of a Buddha out of which Buddhas and indeed all 'phenomena' (Sanskrit: dharmas) arise and to which they return after their dissolution. Buddhas are manifestations of the Dharmakaya called Nirmanakayas. Unlike ordinary unenlightened persons, Buddhas (and arhats) do not die (though their physical bodies undergo the cessation of biological functions and subsequent disintegration). In the Lotus Sutra (sixth fascicle) Buddha explains that he has always and will always exist to lead beings to their salvation. This eternal aspect of Buddha is the Dharmakaya. The Dharmakaya may be considered the most sublime or truest reality in the Universe corresponding closely to the post-Vedic conception of Brahman and that of the Father in the Christian Trinity.
Tibetan: chos sku "Chos" (Tibetan) holds the semantic field of "dharma" (Sanskrit). "Sku" (Tibetan) holds the semantic field of: "body, form, image, bodily form, figure". Thondup & Talbott (1996, 2002: p.48) render it as the "ultimate body". In a key scholarly collaborative Nyingmapa translation work published in 2005, furthermore notable as the first complete rendering of the Bardo Thodol into the English language from the Tibetan, this technical term was configured into English as "Buddha-body of Reality".
