Cheshvan

Marcheshvan (Hebrew: מַרְחֶשְׁוָן‎, Standard Marḥešvan Tiberian Marḥešwān; from Akkadian waraḫsamnu, literally "eighth month"), sometimes shortened to Cheshvan (חֶשְׁוָן‎, Standard Ḥešvan Tiberian Ḥešwān), is the second month of the civil year (which starts on 1 Tishrei) and the eighth month of the ecclesiastical year (which starts on 1 Nisan) on the Hebrew calendar.

In a regular (kesidran) year Marcheshvan has 29 days, but because of the Rosh Hashanah postponement rules, in some years an additional day is added to Marcheshvan to make the year a "full" (maleh) year. Marcheshvan is an autumn month which occurs in October–November in the Gregorian calendar.

Given the Akkadian etymology, it seems likely the מ‎ and the ו‎ were switched at some point in time, since w-r-ḥ is the Semitic root for "moon" (and thus also "month"), and š-m-n is the Semitic root for "eight". Also, מ‎ and ו‎ are labials. Since then, the first two letters מַר‎ (mar) have been reinterpreted as the Hebrew word for bitter, alluding to the fact that the month has no holidays or fasts.

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