FreyayoudaoicibaDictYouDict[Freya 词源字典]
goddess of sexual love and beauty in Norse mythology, from Old Norse Freyja, which is related to Old English frea "lord;" Old Saxon frua, Middle Dutch vrouwe "woman, wife," German Frau; see frau).
Frigga is usually considered the goddess of married love; Freya, the goddess of love, the northern Venus. Actually, Frigga is of the Aesir family of Scandinavian myth; Freya, of the Vanir family; the two lines of belief merged, and the two goddesses are sometimes fused, and sometimes confused. [Joseph T. Shipley, "The Origins of English Words," 1984]
[Freya etymology, Freya origin, 英语词源]
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).