The mahzor (alternately machzor, plural mahzorim, Hebrew מחזור, pronounced [maχˈzor] and [maχzoˈrim], respectively) is the prayer book used by Jews on the High Holidays of Rosh Hashanah and Yom Kippur. Many Jews also make use of specialized mahzorim on the three "pilgrimage festivals" of Passover, Shavuot, and Sukkot. The prayer book is a specialized form of the siddur, which is generally intended for use in weekday and Shabbat services.The word mahzor means "cycle" (the root Ħ-Z-R means "to return"). It is applied to the festival prayer book because the festivals recur annually.