Lama, from the Tibetan for none higher, denoting one who has no superior in spiritual attainment, is used broadly across the four principal schools of Tibetan Buddhism, Nyingma, Kagyu, Sakya and Gelug, for a qualified teacher, though the specific standards for who may properly be addressed as lama vary meaningfully between the schools: some communities apply the title relatively broadly to any ordained teacher who has completed a defined course of study and practice, such as a multi-year meditation retreat, while others reserve it more narrowly for teachers who have received specific formal authorization, often through empowerments and direct transmission, from an already-recognized lama.
Contrary to a common Western misconception, lama does not denote a fixed, singular rank equivalent to priest or bishop, nor is it synonymous with tulku, the specifically reincarnation-based title: a lama may or may not also be a recognized tulku, and a tulku, particularly a young child only recently recognized, may not yet have completed the study and practice a community would otherwise require before conferring the title lama on its own merits, meaning the two titles, though frequently held together by senior teachers, denote genuinely separate qualifications, one based on demonstrated learning and practice, the other on a claimed reincarnation.