A bhikkhu (Pali: भिक्खु, Sanskrit: भिक्षु, romanized: bhikṣu) is an ordained male in Buddhist monasticism. Male, and female monastics (bhikkhunī), are members of the Sangha (Buddhist community).
The lives of all Buddhist monastics are governed by a set of rules called the prātimokṣa or pātimokkha. Their lifestyles are shaped to support their spiritual practice: to live a simple and meditative life and attain nirvana.
Buddhist monasticism is one of the earliest surviving forms of organized monasticism and one of the fundamental institutions of Buddhism. Monks and nuns, called bhikkhu (Pali, Skt. bhikshu) and bhikkhuni (Skt. bhikshuni), are responsible for the preservation and dissemination of the Buddha's teaching and the guidance of Buddhist lay people. Three surviving traditions of monastic discipline (Vinaya), govern modern monastic life in different regional traditions: Theravada (Sri Lanka and Southeast Asia), Dharmaguptaka (East Asia), and Mulasarvastivada (Tibet and the Himalayan region).
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