अग्निनिचयः (Agninichaya) / The Accumulation of Sacred Fire & the Classification of Pitṛs by Time-Order
वायुः प्रजापतिर्भूतो लोकात्मा प्रपितामहः / अहोरात्रकरस्तस्मात्स वायुरनुवत्सरः
vāyuḥ prajāpatirbhūto lokātmā prapitāmahaḥ / ahorātrakarastasmātsa vāyuranuvatsaraḥ
Vāyu, becoming Prajāpati, is the Soul of the worlds, the primeval grandsire; he fashions day and night—therefore Vāyu is called Anuvatsara.