Matsyapurana 128.27

128.27

bhidyate ṛtumāsādya sahasraṃ bahudhā punaḥ
ityevaṃ maṇḍalaṃ śuklaṃ bhāsvaraṃ lokasaṃjñitam //

Having reached the seasons, the thousand [rays] are divided again in various ways. / Thus the white, radiant disc is named 'the world';