Nirmāṇakāya (Chinese: 應身; pinyin: yīngshēn; Tibetan: སྤྲུལ་སྐུ་, tulku, Wylie: sprul sku) is the third aspect of the trikāya and the physical manifestation of a Buddha in time and space.
"[2] One early Buddhist text, the Pali Samaññaphala Sutta, lists the ability to create a “mind-made body” (manomāyakāya) as one of the "fruits of the contemplative life".
4th to 5th century CE) defined nirmita as a siddhi or psychic power (Pali iddhi, Sanskrit: ṛddhi) developed through Buddhist discipline, concentrated discipline (samadhi) and wisdom in his seminal work on Buddhist philosophy, the Abhidharmakośakārikā.
According to Jigme Lingpa, nirmanakaya (emanations) appear "according to the different perceptions, dispositions, and aspirations" of sentient beings.
He also states that "their enlightened activities, which remove the delusions of samsara, are as limitless as the boundless reaches of space.