FridayyoudaoicibaDictYouDict[Friday 词源字典]
Friday: [OE] Friday was named for Frigg, in Scandinavian mythology the wife of Odin and goddess of married love and of the hearth (Frigg, or in Old English Frīg, is thought to have come from prehistoric Germanic *frijaz ‘noble’, source of English free). ‘Frigg’s day’ was a direct adaptation of Latin Veneris dies ‘Venus’s day’ (whence French vendredi ‘Friday’), which in turn was based on Greek Aphrodítēs hēméra ‘Aphrodite’s day’.
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Friday (n.)youdaoicibaDictYouDict
sixth day of the week, Old English frigedæg "Friday, Frigga's day," from Frige, genitive of *Frigu (see Frigg), Germanic goddess of married love. The day name is a West Germanic translation of Latin dies Veneris "day of (the planet) Venus," which itself translated Greek Aphrodites hemera.

Compare Old Norse frijadagr, Old Frisian frigendei, Middle Dutch vridach, Dutch vrijdag, German Freitag "Friday," and the Latin-derived cognates Old French vendresdi, French vendredi, Spanish viernes. In Germanic religion, Freya (q.v.) corresponds more closely in character to Venus than Frigg does, and some early Icelandic writers used Freyjudagr for "Friday."

A fast-day in the Church, hence Friday face (17c.) for a gloomy countenance. Black Friday as the name for the busy shopping day after U.S. Thanksgiving holiday is said to date from 1960s and perhaps was coined by those who had the job of controlling the crowds, not by the merchants; earlier it was used principally of Fridays when financial markets crashed (1866, 1869, 1873).