sushupti

सुषुप्ति suṣupti

Deep dreamless sleep, awareness without objects; the third of the four states in the Mandukya Upanishad, mapped to the sound M of OM.

Where this term appears

Not This, Not This Treatise
The third is sushupti , deep dreamless sleep, in which there are no objects at all, neither outer nor inner, and awareness rests as an undivided mass, the text says, a state of peace from which one wakes saying…
Dakshinamurti: Shiva as the silent guru Deities
Another reads them as the three ordinary states, jagrat , waking, svapna , dream, and sushupti , deep sleep, the three the self passes through and is never confined to.
The Three Cities Treatise
The first reading is the three states of consciousness - jagrat (waking), svapna (dreaming), sushupti (deep sleep).