A hill near Gayá. Here the Buddha came from Uruvelá after converting the Tebhátika-Jatilá, and here he lived with one thousand monks. On this occasion of his coming he preached the Adittapariyáya Sutta (Vin.i.34f; S.iv.19f; J.i.82; AA.i.57, etc.; PvA.21; Ud.i.9; DhA.i.72).
When Devadatta managed to win over five hundred of the monks to his side, it was to Gayásísa that he retired with them, and there it was that the Buddha's Chief Disciples had to go to reclaim them (Vin.ii.199; DhA.i.121; J.i.142, 425, 490f; iv.180). It is said (J.i.185, 508; ii.38f) that Ajátasattu built a special monastery for Devadatta at Gayásísa.
The Commentaries (SA.iii.4; UdA.74) say that the hill was so called because it was composed of a flat stone and was shaped like an elephant's head (gaja-sísa-sadisa-pitthipásáno). There was room on the rock for one thousand monks.
The hill stands about one mile to the south-west of Gayá and is now called Brahmayoni. To the south-east of the hill Hiouen Thsang saw the three thúpas of the Tebhátika Jatilá (CAGI.524f).
See also Gayá Sutta.