Nusach Sefard

Nusach Sefard is the name for various forms of the Jewish siddur, designed to reconcile Ashkenazi customs (Hebrew: מנהג "Custom", pl. minhagim) with the kabbalistic customs of the Ari. To this end it has incorporated the wording of Nusach Edut haMizrach, the prayer book of Sefardi Jews, into certain prayers. Nusach Sefard is used nearly universally by Hasidim, as well as by some other Ashkenazi Jews: it has not gained significant acceptance by Sephardi Jews. Each Hasidic dynasty uses its own version of the Nusach Sefard siddur, often with great divergence between different versions.

Read more about Nusach Sefard:  Prayers and Customs, History