rtsa gsum

རྩ་གསུམ
1) the three nadis --lus kyi rtsa ro ma dang, rkyang ma, dbu ma; 2) the three roots guru, yidam, dakini [+ dharmapala] producers of dharma, the root of blessing is the guru, the root of siddhi the yidam, the root of protection from obstacles the dakini]. (IW)

three roots (bla ma, yi dam, mkha' 'gro). (JV)

1) the three roots, [guru, yidam, dakini [+ dharmapala]. 2) the three channels, ro ma / la la na, rkyang ma / ra sa na, dbu ma / kun 'dar ma / avadhuti]. (RY)

roots, three Guru, yidam, and dharmapala. These three are objects of refuge in the Vajrayana in addition to the Three Jewels. (RY)