The first moment of the attainment is termed the path of stream-entry (sotāpatti-magga), which cuts through the first three fetters. The person who experiences it is called a stream-winner (sotāpanna)...

These four stages are Sotāpanna (stream-enterer), Sakadāgāmi (once-returner), Anāgāmi (non-returner), and Arahant. The oldest Buddhist texts portray the Buddha as referring to people who are at one of these four stages as noble people (ariya-puggala) and the community of such persons as the noble sangha (ariya-sangha)....