Sangha or saṃgha (IPA: [sɐŋɡʱɐ]) is a term meaning "association", "assembly", "company" or "community". In a political context, it was historically used to denote a governing assembly in a republic or a kingdom, and for a long time, it has been used by religious associations, including Buddhists, Jains and Sikhs. Given this history, some Buddhists have stated that the tradition of the sangha represents humanity's oldest surviving democratic institution.

In Buddhism, sangha refers to the monastic communities of bhikkhu (monks) and bhikkhuni (nuns). These communities are traditionally referred to as the bhikkhu-sangha or the bhikkhuni-sangha. As a separate category, those Buddhists who have attained any of the four stages of enlightenment, whether or not they are members of the monastic community, are referred to as the āryasaṅgha ("noble Sangha").

According to the Theravada school and Nichiren Shoshu Buddhism, the term sangha does not refer to the community of unenlightened sāvakas (lay followers) nor does it refer to the community of Buddhists as a whole. Instead, the Theravada school uses the term parisā ("assembly") or catuparisā ("fourfold assembly") to refer to the bhikkhu, bhikkhunī, upāsaka, and upāsikā as a collective.

In a glossary of Buddhist terms, Richard Robinson et al. define sangha as:

Sangha. Community. This word has two levels of meaning:

(1) on the ideal (arya) level, it denotes all of the Buddha’s followers, lay or ordained, who have at least attained the level of srotāpanna;

(2) on the conventional (saṃvṛti) level, it denotes the orders of the Bhikṣus and Bhikṣunis.

Mahayana practitioners may use the word "sangha" as a collective term for all Buddhists, but the Theravada Pāli Canon uses the word parisā (Sanskrit pariṣad) for the larger Buddhist community—the monks, nuns, lay men, and lay women who have taken the Three Refuges—with a few exceptions reserving "sangha" for its original use in the Pāli Canon—the ideal (arya) and the conventional.