即兜率天。欲界諸天之一。其義為妙足。亦譯知足。謂此天人。於五欲皆知足也。
(兜率 or 兜率哆); 兜術; 珊都史多, 珊覩史多; 鬥瑟多 Tuṣita, from tuṣ, contented, satisfied, gratified; name of the Tuṣita heaven, the fourth devalokain the 欲界 passion realm, or desire realm between the Yama and Nirmāṇarati heavens. Its inner department is the Pure Land of Maitreya who, like Śākyamuni and all Buddhas, is reborn there before descending to earth as the next Buddha; his life there is 4,000 Tuṣita years (each day there being equal to 4000 earth-years) 584 million such years.
兜率陀 此云妙足。新云睹史陀，此云知足。西域記云：睹史多，舊曰兜率陀。兜術陀，訛也。於五欲知止足故。佛地論：名[喜/心]足，謂後身菩薩，於中教化，多修[喜/心]足故。
梵語上界天名也唐云知足