Nusach (Jewish custom)

In Judaism, a nusach or nusakh (Hebrew: נוסח, romanizednusáḥ, Yiddish: נוסח, romanizednúsekh, pl. נוסחים nusaḥim, Yiddish: נוסחאות, romanizednuskhóes) is the exact text of a Jewish prayer service, sometimes translated as "rite". Nusach may more accurately translate to "formulation" or "wording".

The texts of siddurim used by the array of Jewish ethnic divisions and religious movements include Baladi-rite prayer, nusach Ashkenaz, nusach Sefard, nusach edot haMizraḥ, Italian nusach, and nusach Ari.

A textual nusach is distinct from a musical nusach, the latter referring to a community's musical style or tradition, particularly the chanted melodies used for the Amidah and other recitative prayers.