The three natures, or “bodies,” of buddhas. The three kayas are the nirmanakaya, or emanation body, by which buddhas appear in physical form in the realm of sentient beings; the samboghakaya, or enjoyment body, through which buddhas appear to bodhisattvas; and the dharmakaya, or truth body, which is the ultimate nature of buddhahood, the unoriginated wisdom beyond form, which manifests in the sambhogakaya and the nirmanakaya. There is a fourth kaya, the svabhavikakaya, or the body of essential nature, and it expresses the ultimate unity of the three aforementioned kayas. The term rupakaya, “form body,” refers to both the sambhogakaya and the nirmanakaya. There is a fifth kaya as well, the mahasukhakaya, or body of great bliss, which is the quality of the other four kayas combined.