bskal pa gsum ldan - (tretayuga) [the kalpa of keeping three [precepts or in Kalachakra when the rigdens control 3/4 of the earth] [IW]
bskal pa gsum ldan - (tretayuga [IW]
dus bzhi - 1) four times: past, present, future, and indefinite time. 2) four seasons. 3) four ages: the perfect age {rdzogs ldan} kritayuga. the threefold age tretayuga {gsum ldan} the twofold age dvaparayuga {gnyis ldan} and the age of degeneration {rtsod ldan} kaliyuga. seasons [RY]
dus bzhi - 1) four ages/ times/ seasons [gold, silver, bronze, iron; the perfect age {rdzogs ldan} or krtayuga, the third age {tretayuga} or {gsum ldan} the second age {gnyis ldan} or dv parayuga, and the age of degeneration {rtsod ldan} or kaliyuga); 2) the four times [past, present, future and indefinite time); 3) the four seasons [dpyid, dbyar, ston, dgun also different periods of the buddhas teaching etc) [IW]
sum ldan - tretayuga group of three, SA bskal pa bzhi, dus bzhi [JV]
gsum ldan - 1) Tretayuga. the third age of the aeon, which is ideally suited to the practice of Yogatantra. 2) the teachings of the three yanas. 3) See {gsum ldan rdo rje 'dzin pa} [RY]