三千大千界(sān qiān dà qiān jiè) “a world system consisting of a triple-thousand great one-thousand worlds,
i.e. trichiliocosm, the whole universe”
Cf. 大千界(dà qiān jiè), 三千大千世界(sān qiān dà qiān shì jiè) etc.; not found at HD. 1.177.; not found at DK. 1.159.;
48b10.三千大千界 内外諸音聲 下至阿鼻獄 上至有頂天 皆聞其音聲 而不壞耳根(v)
K. 359.9.trisāhasra~ ... kṣetra~; Z. 120a2.(一切)三千 是佛國土;