Sabbath a synonym of midnight-to-midnight "Saturday" (literally, Saturn's day in at least a dozen languages): this is a simplification of the use of "Sabbath" in other religious contexts, where the two do not coincide. (Using midnight instead of sundown as delimiter dates back to the Roman Empire.) In over thirty other languages, the common name for this day in the seven-day week is a cognate of "Sabbath". "Sabbatini", originally "Sabbadini", often "Sabatini", etc., is a very frequent Italian name form ("Sabbatos" is the Greek form), indicating a family whose ancestor was born on Saturday, Italian "sabato"; "Domenico" indicated birth on Sunday.
Determination of the day of the week that a year can start on, and leap years will alter the day of the week after February 29. This means that there are 14 configurations that a year can have. All the configurations can be referenced by a dominical letter, but as February 29 has no letter allocated to it a leap year has two dominical letters, one for January and February and the other (one step back in the alphabetical sequence) for March to December. For example, 2018 is a common year starting on Monday, meaning that 2018 corresponds to the 2007 calendar year and with the last