cosmological

युग yuga

yuga

root √yuj — to yoke, join — hence "an age," "a period yoked to a quality"

A cosmic age. The four yugas — Kṛta, Tretā, Dvāpara, Kali — cycle in declining length and rectitude.

Time in the epic is structured by yugas — successive cosmic ages, each shorter and more compromised than the last. The four are:

Kṛta-yuga — the perfected age. Dharma stands on all four legs.
Tretā-yuga — three legs.
Dvāpara-yuga — two legs. The Mahābhārata is set at its end.
Kali-yuga — one leg. The age that begins after Kṛṣṇa’s death.

The schema is a moral cosmology, not a calendar. The text’s anxiety about dharma — about whether kings still know what is right, whether vows still hold, whether asceticism still works — is the anxiety of a Dvāpara-yuga narrator looking forward into Kali. The war itself is the hinge.

A manvantara is a longer cycle (the reign of one Manu); a kalpa is a day of Brahmā. The yugas nest inside these. The Mahābhārata is interested mainly in the immediate horizon — what age are we in, and what is no longer possible because of it?