A moniker for a unit
of cosmic time that might have two meanings.
Traditional thinking is that time has no origin or conclusion,
but rather rotates between cycles of creation and activity, followed by halt
and silence.
The active period of each of these cycles is known as the
Day of Brahma, while the calm phase is known as the Night of Brahma.
The Day of Brahma is split into a thousand mahayugas
("great cosmic eras"), each lasting 4.32 million years in cosmic
time, and this is one probable definition of the term yuga.
The term is most often used to refer to the Krta Yuga, Treta
Yuga, Dvapara Yuga, and Kali Yuga, which are the four yugas that make up a
mahayuga.
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