Bittul ha-yesh, the nullification of something-ness, is a Hasidic ideal, especially in Chabad. The worshipper recognizes that nothing exists apart from God and dissolves the sense of independent self, becoming a vessel for the divine. It has been compared with the Sufi fanāʾ.
Bittul
Self-nullification: the Hasidic practice of annulling the ego before God.
Also: bittul ha-yesh