WednesdayyoudaoicibaDictYouDict[Wednesday 词源字典]
Wednesday: [OE] The Romans called the middle day of the week Mercurii diēs ‘Mercury’s day’ (source of French mercredi, Italian mercoledì, and Spanish miercoles). The Germanic peoples equated Mercury with their own god Woden or Odin (whose name may etymologically mean the ‘inspired or mad one’), and they translated the Latin term accordingly, giving Dutch woensdag, Swedish and Danish onsdag, and English Wednesday.
[Wednesday etymology, Wednesday origin, 英语词源]
Wednesday (n.)youdaoicibaDictYouDict
fourth day of the week, Old English wodnesdæg "Woden's day," a Germanic loan-translation of Latin dies Mercurii "day of Mercury" (compare Old Norse Oðinsdagr, Swedish Onsdag, Old Frisian Wonsdei, Middle Dutch Wudensdach). For Woden, see Odin.

Contracted pronunciation is recorded from 15c. The Odin-based name is missing in German (mittwoch, from Old High German mittwocha, literally "mid-week"), probably by influence of Gothic, which seems to have adopted a pure ecclesiastical (i.e. non-astrological) week from Greek missionaries. The Gothic model also seems to be the source of Polish środa, Russian sreda "Wednesday," literally "middle."