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late 14c., from Latin februarius mensis "month of purification," from februa "purifications, expiatory rites" (plural of februum), of unknown origin, said to be a Sabine word. The last month of the ancient (pre-450 B.C.E.) Roman calendar, so named in reference to the Roman feast of purification, held on the ides of the month. In Britain, replaced Old English solmonað "mud month." English first (c.1200) borrowed it from Old French Feverier, which yielded feoverel before a respelling to conform to Latin.
second month of the Gregorian calendar. It was named after Februalia, the Roman festival of purification. Originally, February was the last month of the Roman calendar.