The story
Borrowed (possibly via Yiddish) from Hebrew אדמו״ר, abbreviation of אדוננו מורנו ורבנו (“our master, teacher and rabbi”).
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A Hasidic rebbe, the leader of a Hasidic court. Full definition →
Borrowed (possibly via Yiddish) from Hebrew אדמו״ר, abbreviation of אדוננו מורנו ורבנו (“our master, teacher and rabbi”).
Etymology from Wiktionary, CC BY-SA 4.0.