Cākṣuṣa–Vaivasvata Manvantara Transition, Deva-Gaṇa Taxonomy, and Loka-Triad Etymology
Bhūr–Antarikṣa–Dyu
भूर्लोको ऽयं स्मृतो भूतमन्तरिक्षं भवत्स्मृतम् / भव्यं स्मृतं दिवं ह्येतत्तेषां वक्ष्यामि साधनम्
bhūrloko 'yaṃ smṛto bhūtamantarikṣaṃ bhavatsmṛtam / bhavyaṃ smṛtaṃ divaṃ hyetatteṣāṃ vakṣyāmi sādhanam
This Bhūrloka is remembered as the past, and the mid-region (antarikṣa) as the present. Heaven is remembered as the future; now I shall speak of the means pertaining to them.