Sat is a
Sanskrit word meaning "the true essence (nature)" and that "which is unchangeable" of an entity, species or existence.
Sat is a common prefix in ancient Indian literature and variously implies that which is good, true, virtuous, being, happening, real, existing, enduring, lasting, essential. In ancient texts, fusion words based on
Sat, refer to "Universal Spirit, Universal Principle, Being, Soul of the World,
Brahman".