Thursday "xoves" and Romanian "joi". This is also reflected in the p-Celtic Welsh "dydd Iau". The astrological and astronomical sign of the planet Jupiter (♃) is sometimes used to represent Thursday. Since the Roman god Jupiter was identified with Thunor (Norse Thor in northern Europe), most Germanic languages name the day after this god: "Torsdag" in Danish, Norwegian, and Swedish, "Hósdagur"/"Tórsdagur" in Faroese, "Donnerstag" in German or "Donderdag" in Dutch. Finnish and Northern Sami, both non-Germanic (Uralic) languages, uses the borrowing "Torstai" and "Duorastat". In the extinct Polabian Slavic language, it was "perundan", Perun being the Slavic equivalent of Thor. There
Determination of the day of the week ISO 8601. The day designated with 7 may also be counted as "0", by applying the arithmetic modulo 7, which calculates the remainder of a number after division by 7. Thus, the number 7 is treated as 0, 8 as 1, 9 as 2, 18 as 4 and so on. If Sunday is counted as day 1, then 7 days later (i.e. day 8) is also a Sunday, and day 18 is the same as day 4, which is a Wednesday since this falls three days after Sunday. The basic approach of nearly all of the methods to calculate the