1. Dhammaruci.-One of the heterodox sects of Ceylon which branched off from the Theravāda (Mhv.v.13).
According to the Nikāya Sangraha (p.11) this secession took place four hundred and fifty-four years after the death of the Buddha, and in the fifteenth year of the reign of Vattagāmani Abhaya. The Nikāya Sangraha gives an account of the origin of this sect. A monk called Mahā-Tissa, incumbent of Abhayagiri, was convicted of living in domestic intercourse and expelled by the Mahāvihāra fraternity. He thereupon left with his followers and lived apart at Abhayagiri. They were strengthened by the arrival of some monks from Pallarārāma in South India, descendants of the Vajjiputtakas. Their teacher was Dhammaruci, and when they joined the Abhayagiri monks, Mahā-Tissa himself took the name of Dhammaruci and his followers became known as Dhammarucikas.
The Mahāvamsa Tīkā (p.176) says that Dhammarucika was the name given to the monks of Abhayagiri when they seceded from the Mahāvihāra, and gives elsewhere (p.676f) the points on which they differed from the Theravādins. These points concerned minor teachings of the Vinaya. The Dhammarucikas became active in the time of Meghavannābhaya, and the king, after an enquiry into the matter, sent sixty of them into exile. They again became powerful in the time of Mahāsena, through the influence of Sanghamitta, and almost succeeded in destroying the Mahāvihāra. But this disaster was averted by the intervention of the king's friend and counsellor, Meghavannābhaya, and Sanghamitta was killed by one of the queens (Mhv.xxxvii.17ff).
In spite of Sanghamitta's untimely end, the Dhammarucikas seem to have enjoyed favour in Ceylon during a long period. Dhātusena gave over to them the Ambatthala-vihāra, which he built on Cetiyapabbata (Cv.xxxviii.75), and Kassapa I, bestowed on them the vihāra he built in the Niyyanti garden, and made all provisions for their comfort (Cv.xxxix.17). Moggallāna I, gave over to them the Dalha-vihāra (Cv.xxxix.41) and Aggabodhi V. the Rājinādīpika-vihāra (Cv.xlviii.1). Sena Ilanga, general of Kassapa IV., built for them the Dhammārāma and the Hadayunha-parivena (Cv.lii.17, 18).
The Sāgaliyas were an offshoot of the Dhammarucikas.
2. Dhammaruci Thera.-An arahant. In the time of Dipankara Buddha he was a young man named Megha, and on hearing the Buddha's declaration regarding Sumedha, he entered the Order under the latter. But, owing to wrong association, he left the Order and murdered his mother. For this he suffered in Avīci and was later born as a fish. One day he heard some shipwrecked sailors calling on the name of Gotama Buddha for protection, and, remembering Dipankara's prophecy, the fish died. He was then born in Sāvatthi, and hearing the Buddha preach at Jetavana, he entered the Order and became an arahant. Ap.ii.429f.
3. Dhammaruci.-A Nāga king who gave grass to Atthadassī Buddha for his seat. BuA.178.