svābhāvika-kāya (Sanskrit). The ‘embodiment of Buddhahood in its essence’, a term first attested in the Abhisamaya-alaṃkāra. The precise nature of this embodiment became a source of controversy in Mahāyāna Buddhism as a result of Haribhadra's textual exegesis which deemed it to be an additional unitary aspect of Buddhahood underlying the standard ‘three bodies’ (trikāya). This was in contrast to the majority view that the term is merely a synonym for absolute reality or the dharma-kāya.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)