rebbe come from the same root Hebrew word, rav, meaning teacher or spiritual guide. Both terms can refer to a teacher of Torah, a personal mentor or teacher, or a spiritual leader.
Rabbi is the commonly used word to describe a teacher or mentor in most modern Jewish movements. Rebbe is a Yiddish-German word that connotes a spiritual leader and master of theology in the Hasidic movement. Hasidic Jews refer to the leaders of different Hasidic dynasties as rebbes. A rebbe is required to be a tzaddik, or
righteous man, in the eyes of God. Rebbes are also sometimes associated with the Baal Shem Tov who Tzvi Freeman noted
was a teacher who not only touched your mind and heart.