Saturday

The English word Saturday begins with the Roman god Saturn. In Latin, the day was called Saturni dies, literally "Saturn's day." That name was current in the Roman world by late antiquity. Unlike most weekday names in English, this one kept the Roman divine name rather than replacing it with a Germanic equivalent.

When Latin Christian culture met early English speech, the name moved into Old English as Saeternesdaeg and related spellings. Written forms appear in Anglo-Saxon England by the early medieval period. The first part points back to Saturn, while the second is daeg, "day." The borrowed structure stayed unusually close to the Latin original.

Other English weekday names were remodeled through Germanic gods: Tuesday, Wednesday, Thursday, and Friday all show that pattern. Saturday was the exception. Old Norse and some continental Germanic traditions had forms linked to bathing or washing for this day, but English did not adopt those. English kept Saturn in place and carried the Roman inheritance forward.

Over time, Saeternesdaeg contracted through Middle English spellings such as Saterday and Saturdai. Sound change and spelling standardization produced modern Saturday by the early modern period. The word now names the seventh day of the week in most English-speaking calendars. Its form still preserves a direct line from Roman religion into everyday English speech.