Thero (Sinhalese: ස්ථවිර, also called Thera, feminine form Theri) is an honorific term for higher ordained Buddhist monks in the Buddhist monastic order. The feminine term, Theri is used for higher ordained Buddhist nuns. The Pāli language term Thera translates to English as 'elder and venerable'. These terms which are used at the end of a monk or a nun's other names, are useful to distinguish Buddhist monastics from the lay people (upāsaka and upāsikā), who keep five precepts. The term Mahathera (feminine form : Mahatheri) is used sometimes to refer most elderly and venerable monks, who have reached a higher level of spiritual development. Usage of these terms varies according to the Buddhist tradition and culture. In Sri Lankan Theravada Buddhist tradition, these terms are widely used.
Some prominent theros / theris :