尼散月（希伯来语：נִיסָן‎，和合本常译作“正月”，或称作“亚笔月”）是希伯来历的一个月份，为犹太教历一月、犹太国历七月，长为30天，对应格里历的3月至4月间。

• 14日：逾越节。
• 15日-21日：除酵节。

Nisan (or Nissan; Hebrew:נִיסָן‎, Standard Nisan Tiberian Nîsān) on the Assyrian calendar is the first month, and on the Hebrew calendar is the first month of the ecclesiastical year and the seventh month (eighth, in leap year) of the civil year. The name of the month is of Assyrian-Babylonian origin; in the Torah it is called the month of the Aviv. Assyrians today refer to the month as the "month of happiness." It is a spring month of 30 days. (Nisan usually falls in March–April) on the Gregorian calendar. In the Book of Esther in the Tanakh it is referred to as Nisan. Karaite Jews interpret it as referring to the month in which barley was ripe.