The term for the initial phase in the formation of the cosmos in some tantra traditions, notably the Trika school of Kashmiri Shaivism.
The Ultimate Reality, imagined as Shiva, is entirely
nondual, and hence neither masculine nor feminine, according to the Trika
school.
The divine awareness becomes cognizant of itself via the
reflection (vimarsha) of its initial illumination, which is the first stage
in cosmological progression (prakasha).
The unqualified divine entity, moved by self-awareness,
develops into a divine being with a male and feminine essence, the first of
many such bipolar dyads from which the cosmos emerges.
Sadashiva is the male half of this primordial dyad, and he
is regarded the universe's material cause.
Shakti, the feminine aspect of the dyad, provides the
creative and dynamic energy for creation.
See Jaideva Singh's Pratyabhijnanahrdayam, 1982, for further
details.
