Adar I

Adar (Hebrew: אֲדָר‎ Adar; from Akkadian adaru) is the sixth month of the civil year and the twelfth month of the ecclesiastical year on the Hebrew calendar. It is a winter month of 29 days. The Month of Adar in the Holy Scriptures comprises in Esther 09, 21.

In leap years, it is preceded by a 30-day intercalary month named Adar Aleph (Hebrew: אדר א'‎, Aleph being the first letter of the Hebrew alphabet, also known as "Adar Rishon" (First Adar) or "Adar I") and it is then itself called Adar Bet (Hebrew: אדר ב'‎, Bet being the second letter of the Hebrew Alphabet, also known as "Adar Sheni" (Second Adar) or "Adar II"). Occasionally instead of Adar I and Adar II, "Adar" and "Ve'Adar" are used (Ve means 'and' thus: And Adar). Adar I and II occur during February–March on the Gregorian calendar.

Based on a line in the Mishnah declaring that Purim must be celebrated in Adar II in a leap year (Megillah 1:4), Adar I is considered the "extra" month. As a result, someone born in Adar during a non leap year would celebrate his birthday in Adar II during a leap year. However, someone born during either Adar in a leap year will celebrate his birthday during Adar in a non-leap year, except that someone born on 30 Adar I will celebrate his birthday on 1 Nisan in a non-leap year because Adar in a non-leap year has only 29 days.

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