Entries related to weekday
Old English wucu, wice, etc., from Proto-Germanic *wikō(n)- (source also of Old Norse vika, Old Frisian wike, Middle Dutch weke, Old High German wecha, German woche), probably originally with the sense of "a turning" or "succession" (compare Gothic wikon "in the course of," Old Norse vika "sea-mile," originally "change of oar," Old English wican "yield, give way"), from PIE root *weik- (2) "to bend, to wind." The vowel sound seems to have been uncertain in Old and Middle English and -e-, -i-, -o-, -u-, -y-, and various diphthongs are attested for it.
"Meaning primarily 'change, alteration,' the word may once have denoted some earlier time division, such as the 'change of moon, half month,' ... but there is no positive evidence of this" [Buck]. No evidence of a native Germanic week before contact with the Romans. The seven-day week is ancient, probably originating from the 28-day lunar cycle, divisible into four periods of seven day, at the end of each of which the moon enters a new phase. Reinforced during the spread of Christianity by the ancient Jewish seven-day week.
As a Roman astrological convention it was borrowed by other European peoples; the Germanic tribes substituting their own deities for those of the Romans, without regard to planets. The Coligny calendar suggests a Celtic division of the month into halves; the regular Greek division of the month was into three decades; and the Romans also had a market week of nine days. Phrase a week, as in eight days a week recorded by 1540s; see a- (1).
Greek planetary names [for the days of the week] ... are attested for the early centuries of our era, but their use was apparently restricted to certain circles; at any rate they never became popular. In Rome, on the other hand, the planetary names became the established popular terms, too strongly intrenched to be displaced by the eccl[esiastical] names, and spreading through most of western Europe. [Carl Darling Buck, "A Dictionary of Selected Synonyms in the Principal Indo-European Languages," 1949]
Old English dæg "period during which the sun is above the horizon," also "lifetime, definite time of existence," from Proto-Germanic *dages- "day" (source also of Old Saxon, Middle Dutch, Dutch dag, Old Frisian di, dei, Old High German tag, German Tag, Old Norse dagr, Gothic dags), according to Watkins, from PIE root *agh- "a day." He adds that the Germanic initial d- is "of obscure origin." But Boutkan says it is from PIE root *dhegh- "to burn" (see fever). Not considered to be related to Latin dies (which is from PIE root *dyeu- "to shine").
Meaning originally, in English, "the daylight hours;" it expanded to mean "the 24-hour period" in late Anglo-Saxon times. The day formerly began at sunset, hence Old English Wodnesniht was what we would call "Tuesday night." Names of the weekdays were not regularly capitalized in English until 17c.
From late 12c. as "a time period as distinguished from other time periods." Day-by-day "daily" is from late 14c.; all day "all the time" is from late 14c. Day off "day away from work" is attested from 1883; day-tripper first recorded 1897. The days in nowadays, etc. is a relic of the Old English and Middle English use of the adverbial genitive.
All in a day's work "something unusual taken as routine" is by 1820. The nostalgic those were the days is attested by 1907. That'll be the day, expressing mild doubt following some boast or claim, is by 1941. To call it a day "stop working" is by 1919; earlier call it a half-day (1838). One of these days "at some day in the near future" is from late 15c. One of those days "a day of misfortune" is by 1936.