Dhammaruci Nikāya. One of the heterodox sects of Sri Lanka which branched off from the Theravāda. This division supposedly took place 450 years after the death of the Buddha. Some sources affirm that Dhammarucika was the name given to the monks of the Abhayagiri when they seceded from the Mahāvihāra, but the traditional accounts of the origins of the group cannot be relied on. Despite some ups and downs in their fortunes, the Dhammarucikas enjoyed favour in Sri Lanka over a long period, with several kings making provisions and donating monasteries to them.

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