Ajaan (Thai): Teacher; mentor. Pāli form: Ācariya.

Arahant: A “worthy one” or “pure one;” a person whose mind is free of defilement and thus is not destined for further rebirth. A title for the Buddha and the highest level of his noble disciples. Sanskrit form: Arhat.

Brahman: A member of the priestly caste, which claimed to be the highest caste in India, based on birth. In a specifically Buddhist usage, “brahman” can also mean an arahant, conveying the point that excellence is based not on birth or race, but on the qualities attained in the mind.

Dhamma: (1) Event; action; (2) a phenomenon in and of itself; (3) mental quality; (4) doctrine, teaching; (5) nibbāna (although there are passages describing nibbāna as the abandoning of all dhammas). When capitalized in this book, Dhamma means teaching. Sanskrit form: Dharma.

Jhāna: Mental absorption. A state of strong concentration, devoid of sensuality or unskillful thoughts, focused on a single physical sensation or mental notion which is then expanded to fill the whole range of one’s awareness. Jhāna is synonymous with right concentration, the eighth factor in the noble eightfold path. Sanskrit form: Dhyāna.

Kamma: Intentional act. Sanskrit form: Karma.

Nibbāna: Literally, the “unbinding” of the mind from passion, aversion, and delusion, and from the entire round of death and rebirth. As this term also denotes the extinguishing of a fire, it carries connotations of stilling, cooling, and peace. “Total nibbāna” in some contexts denotes the experience of Awakening; in others, the final passing away of an arahant. Sanskrit form: Nirvāṇa.

Pāli: The language of the oldest extant complete Canon of the Buddha’s teachings.

Pāṭimokkha: The basic code of rules for monks and nuns. The monks’ code contains 227 rules; the nuns’, 311.

Saṁvega: A sense of overwhelming terror or dismay over the pointlessness of life as it is normally lived.

Saṅgha: On the conventional (sammati) level, this term denotes the communities of Buddhist monks and nuns. On the ideal (ariya) level, it denotes those followers of the Buddha, lay or ordained, who have attained at least stream-entry.

Sutta: Discourse. Sanskrit form: Sūtra.

Tathāgata: Literally, “one who has become authentic (tatha-āgata),” or “one who is really gone (tatha-gata),” an epithet used in ancient India for a person who has attained the highest religious goal. In the Pali Canon, this usually denotes the Buddha, although occasionally it also denotes any of his arahant disciples.

Vinaya: The monastic discipline, whose rules and traditions comprise six volumes in printed text.