Av (,
Standard Av Tiberian Aramaic אבא Abba; from
Akkadian abu; "
father") is the eleventh month of the civil year and the fifth month of the ecclesiastical year on the
Hebrew calendar. The name is Babylonian in origin and appeared in the
Talmud around the 3rd century. This is the only month which is not named in the Bible. It is a summer month of 30 days. Av usually occurs in July–August on the
Gregorian calendar.