The term 'Month on the Hebrew Calendar' refers to the twelve months of the Jewish calendar. ADAR (4 letters) is the twelfth month of the Jewish calendar, which usually falls in February or March. Elul (4 letters) is the sixth month of the Jewish calendar, which usually falls in August or September. Both ADAR and Elul are important months in the Jewish calendar, as they are associated with religious holidays such as Purim and Rosh Hashanah respectively.