leap year แปลว่า

PIE word *yóh₁r̥ From Late Middle English lepe-yer, lep-yer (“year with 366 days, leap year”), from lep, lepe (“act of jumping, jump, leap”) (from Old English hlīep, hlȳp, probably ultimately from Proto-Indo-European *klewp- (“to spring; to stumble”)) + yer (“calendrical unit based on a complete revolution of the Earth around the Sun, year”) (from Old English ġēar, ultimately from Proto-Indo-European *yóh₁r̥ (“year”)). The English term is analysable as leap (noun) + year, and possibly relates to the phenomenon that any fixed date of a 365-day calendar advances one weekday each year but every date of a 366-day year after February 29 (often seen as the leap day) advances by two weekdays instead. For example, Christmas (December 25) fell on a Saturday in 2004, a Sunday in 2005, a Monday in 2006, and a Tuesday in 2007 but then “leapt” over Wednesday to fall on a Thursday in 2008 which was a leap year. Compare also Old English mōnan hlȳp (“moon’s leap”) and Medieval Latin saltus lūnae (literally “leap moon”), an additional day added every 19 years (a Metonic cycle) to bring the lunar and solar calendars into alignment. Cognates * Old Norse hlaup-ár (“leap year”)