Tathagata

[Tathagata is an] epithet of the Buddha that he employed primarily when referring to himself. He also used it to refer to other buddhas who preceded him and who would follow. Tathagatha refers to one who has trod the path to full awakening and so reached the end of suffering and escaped samsara. The implication is that the path is open to all who would follow it. In later Mahayana Buddhism, Tathagata came to mean the essential buddha nature found in everyone. [Source]