A Nigantha who had two interviews with the Buddha, as recorded in the Cūla Saccaka Sutta and Mahā Saccaka Sutta. He is addressed as Aggivessana, that being his gotta name (the Agnivesyāyanas).
Buddhaghosa says (MA.i.450; cf. J.iii.1, where Sivāvatikā is called Avavādakā) that both his parents were Niganthas, skilled debaters, who married at the suggestion of the Licchavis, because they were unable to defeat each other in argument. The Licchavis provided for their maintenance. Four daughters were born to them: Saccā, Lolā, Patācārā and Sivāvatikā. These engaged in a discussion with Sāriputta, and were defeated by him. Having then entered the Order, they became arahants. Saccaka was their brother and was the youngest of them. He was a teacher of the Licchavis and lived at Vesāli.
When Saccaka was defeated by the Buddha as stated in the Cūla-Saccaka Sutta, one of the Licchavis, Dummukha, compared him to a crab in a pool, its claws being smashed one after the other and unable to return to the pool. Saccaka, owned defeat, and begged the Buddha to take a meal at his house. The Buddha agreed, and Saccaka became his follower (M.i.234f).
It is said (MA.i.469f) that, in a later birth, long after the Buddha's death, Saccaka was born in Ceylon as the Thera Kāla Buddharakkhita and attained arahantship.
Saccaka, is identified with Senaka of the Mahā Ummagga Jātaka. J.vi.478.