Hint with an alternative definition: it is a totally pure space (or stark space) with a vast capacity & absence of anything, not occupied.

Hint with composition: peace + pause + total

Hints with translation + consonant words (by sounds or letters): used past is an empty time (no energy) / it is like a passed out place / emptiness is apostate of the essence / pustule with emptiness / super pore space (any content leaks out) / emptiness has stopped & ousted content / Surplus > Paucity > Пустота / it is like a path to a toom place

Hint with a mirror: a tot’ soup in a scoop (rich taste) | пустота (no taste) / put to storage | пустота (no content) / a hotspot place for booze | пустота (no visitors)

Russian pro-tip: путь + сота (путь в пустоту)

Mental visualization: ПУ (empty bags) + СТ (empty overturned bowl)