Definitions for "Mahasiddha"
(Tib. drup chen) A great practitioner who has achieved great realization.
great perfect being” – “great sorcerer” – a highly perfected and accomplished mystic; one of a legendary class of demigods or superhuman Tantric practitioners who propagated Tantra throughout South Asia and Tibet.
a realized being from the history of Buddhism (a tradition which began in India), who usually continued her or his mundane work in the world, like washing clothes or selling wine, but reached realization through that work and attained magical powers