Week

==Days of the week==
Cf. 	Seven days 	Old English	Germanic gods	Greco/Roman gods	Greek 	Latin 	Greco/Roman planets	Eccl. Greek 	Eccl. Latin
1 [日] 햇님 	Sunday Day of the Lord	sunnandæg 	Sun 	Helios/Sol 	ἡμέρα Ἡλίου (iméra ilíu) 	dies Sōlis 	Helios/Sol 	Κυριακὴ ἡμέρα (kiriaki iméra) 	[dies] dominica rarely feria prima, feria dominica
2 [月] 달님 	Monday 	mōnandæg 	Moon 	Selene/Luna 	ἡμέρα Σελήνης (iméra selínis) 	dies Lūnae 	Selene/Luna 	Δευτέρα ἡμέρα (devtéra iméra) 	feria secunda
3 [火] 치우 	Tuesday 	tiwesdæg 	Tiwaz 	Ares/Mars 	ἡμέρα Ἄρεως (iméra áreos) 	dies Martis 	Tolma/Mars 	Τρίτη ἡμέρα (tríti iméra) 	feria tertia
4 [水] 복희 	Wednesday 	wōdnesdæg 	Wodanaz 	Hermes/Mercury 	ἡμέρα Ἑρμοῦ (iméra ermû) 	dies Mercuriī	Ananke/Mercury 	Τετάρτη ἡμέρα (tetárti iméra) 	feria quarta rarely media septimana
5 [木] 헌원 	Thursday 	þunresdæg 	Þunraz 	Zeus/Jupiter 	ἡμέρα Διός (iméra diós) 	dies Iovis 	Nike/Jupiter 	Πέμπτη ἡμέρα (pémpti iméra) 	feria quinta
6 [金] 여와 	Friday 	frīgedæg 	Frige 	Aphrodite/Venus 	ἡμέρα Ἀφροδίτης (iméra afrodítis)	dies Veneris 	Eros/Venus 	Παρασκευὴ ἡμέρα (paraskevi iméra)"day of preparation", i.e. the day before Sabbath, c.f. Luke 23:54 ()	feria sexta
7 [土] 신농 	Saturday Sabbath 	sæterndæg 	— 	Cronus/Saturn 	ἡμέρα Κρόνου (iméra krónu) 	dies Saturnī 	Nemesis/Saturn 	Σάββατον (sábbaton) 	Sabbatum; dies sabbatinus rarely feria septima, feria Sabbati
The days of the week were originally named for [some gods rather than] the classical planets. This statement may not be very true. In Ancient Greek, the planet Jupiter was Νίκη (Níkē), regardless of Dios or Zeus; and the planet Venus was Ἔρως (Érōs), regardless of Aphrodite. Instead, those days were more likely named for some deities. This may well explain be why "An ecclesiastical, non-astrological, system of numbering the days of the week was adopted in Late Antiquity," as separately mentioned elsewhere. The Germanic names of the days of the week are primarily the deities equivalent to the Greco-Roman counterparts rather than planets. This naming system persisted alongside an "ecclesiastical" tradition of numbering the days, in w:ecclesiastical Latin beginning with dominica (the Day of the Lord) as the first day. The Greco-Roman gods associated with the classical planets were rendered in their w:interpretatio germanica at some point during the late Roman Empire, yielding the Germanic tradition of names based on indigenous deities.
The ordering of the weekday names are not that of the classical order of the planets (sorted by distance in the w:planetary spheres model, or, equivalently, by their apparent speed of movement in the night sky). Instead, the w:planetary hours systems resulted in succeeding days being named for planets that are three places apart in their traditional listing. This characteristic was apparently discussed in w:Plutarch in a treatise written in c. AD 100, which is reported to have addressed the question of Why are the days named after the planets reckoned in a different order from the actual order? (the text of Plutarch's treatise has been lost).E. G. Richards, Mapping Time, the Calendar and History, Oxford 1999. p. 269.
An ecclesiastical, non-astrological, system of numbering the days of the week was adopted in Late Antiquity. This model also seems to have influenced (presumably via Gothic) the designation of Wednesday as "mid-week" in Old High German (mittawehha) and Old Church Slavonic (срѣда). Old Church Slavonic may also modelled the name of Monday, понєдѣльникъ, after the Latin feria secunda.Max Vasmer, Russisches etymologisches Wörterbuch, s.v. понедельник; however, the Slavic languages later introduced a secondary numbering system that names Tuesday as the "second day". The ecclesiastical system became prevalent in Eastern Christianity, but in the Latin West it remains extant only in modern Icelandic and Galician-Portuguese.the latter specifically due to the influence of w:Martin of Braga, 6th-century archbishop of Braga. 
 
==Nundinal cycle==
The Romans of the Republic, like the Etruscans, used a "market week" of eight days, marked as A to H in the calendar. A nundinum was the market day; etymologically, the word is related to novem, "nine", because the Roman system of counting was inclusive. The market "week" is the nundinal cycle. Since the length of the year was not a multiple of eight days, the letter for the market day (known as a "nundinal letter") changed every year. For example, if the letter for market days in some year was A and the year was 355 days long, then the letter for the next year would be F.
The nundinal cycle formed one rhythm of day-to-day Roman life; the market day was the day when country people would come to the city, and the day when city people would buy their eight days' worth of groceries. For this reason, a law was passed in 287 BC (the Lex Hortensia) that forbade the holding of meetings of the comitia (for example to hold elections) on market days, but permitted the holding of legal actions. In the late republic, a superstition arose that it was unlucky to start the year with a market day (i.e., for the market day to fall on 1 January, with a letter A), and the pontiffs, who regulated the calendar, took steps to avoid it.
Because the nundinal cycle was absolutely fixed at eight days under the Republic, information about the dates of market days is one of the most important tools used for working out the Julian equivalent of a Roman date in the pre-Julian calendar. In the early Empire, the Roman market day was occasionally changed. The details of this are not clear, but one likely explanation is that it would be moved by one day if it fell on the same day as the festival of Regifugium, an event that could occur at intervals of three years. The reason for this is not explained.
The nundinal cycle was eventually replaced by the modern seven-day week, which first came into use in Italy during the early imperial period,P. Brind'Amour, Le Calendrier romain: Recherches chronologiques (Ottawa, 1983), 256–275 after the Julian calendar had come into effect in 45 BC. The system of nundinal letters was also adapted for the week, see dominical letter. For a while, the week and the nundinal cycle coexisted, but by the time the week was officially adopted by Constantine in AD 321, the nundinal cycle had fallen out of use. For further information on the week, see week and days of the week.
=== See also===
; nundine : (chiefly in Ancient Rome) A market held every eight days
== Notes ==
== Footnotes ==
Category:Words