Kosov is the name of a Hasidic dynasty founded by Rabbi Menachem Mendel Hager of Kosiv, a town in Galicia, presently in Ukraine.
The Kosov Hasidic dynasty, Rabbi Mendel of Kosov's descendants, founded the many Kosov Hasidic sects. The Vizhnitz dynasty is the best known branch of the original Kosover dynasty. Other branches include Seret.
Among the many contemporary descendants of the Kosov dynasty, two are called "the Kosover Rebbe": Rabbi Shraga Feivish Hager of Borough Park, Brooklyn(died 2024), where he had a substantial following and presided at his tish, and Rabbi Menachem Monderer of Jerusalem (died 2013).[1] There is also a historic Kosover synagogue in Tzfas (Safed), Israel, which, however, is run by followers of the Biala Rebbe of Lugano, Switzerland.