GJT: abbr. for "man nas 'debs pa" which means to "purify from below" and refers to the process of filling up, from the bottom up, with the amrita that decends from Vajrasattva. The second of three modes of purification in Vajrasattva practice; the other two are {yan 'debs} and {'phul 'debs}. In the {man 'debs} process one imagines one's impurities float to the crown of one's head where they evaporate or dissipate. N.B. GJT said that "deb" had the sense of "to push" but did not know the spelling of "deb" so {'debs} is a best guess. See also {yan 'debs} and {'phul 'debs} [mss]