Kislev (Hebrew: כִּסְלֵו, Standard Kislev Tiberian Kislēw; also Chislev) is the third month of the civil year and the ninth month of the ecclesiastical year on the Hebrew calendar.

In a regular (kesidran) year Kislev has 30 days, but because of the Rosh Hashanah postponement rules, in some years it can lose a day to make the year a "short" (chaser) year. Kislev is an autumn month which occurs in November–December on the Gregorian calendar and is sometimes known as the month of dreams. The name of the month may be taken from Akkadian kislimu, which means "inspissated, thickened" due to plentiful rains. But the name may also derive from the Hebrew root K-S-L as in the words "kesel, kisla" (hope, positiveness) or "ksil" (Orion, a constellation that shines especially in this month) - because of the expectation and hope for rains.