A friend of mine recently posted where "Monday" was named after. An action that triggered the following post. Let's see how every day of the week got its name.
The ancient Mesopotamians first associated the days of the week with figures from astrology and mythology, and the ancient Romans kept this tradition alive in their own naming conventions. The speakers of other languages, though, swapped the Roman gods and goddesses for some of their own, and that change has had a lasting impact on the names of the days in modern English.
Sun Day and Moon Day
The first two days of the week evoke solar and lunar power, respectively. The ancient Romans celebrated diēs sōlis, meaning “day of the sun.” “Sunday,” as we know it, comes from the Old English word Sunnandæg, which is a translation of the Latin name.
The word “Monday” comes from the Old English word Mōnandæg, meaning “moon's day” (mōna means “moon,” and dæg means “day”). This is a translation of the day’s Latin name, diēs lūnae (“day of the moon”).
Tiu’s Day
The Romans called Tuesday diēs Mārtis (“day of Mars”) in honor of Mars, the Roman god of war. In Old English, Mars was replaced with Tiu (sometimes spelled “Tiw”), the Germanic god of war. As a result, diēs Mārtis became Tīwesdæg in Old English. The names used in Middle English are even closer to our “Tuesday”: Tewesday and Tuesdai.
Woden’s Day
The Latin name for Wednesday is dies Mercurii, meaning “day of Mercury.” In Old English, “Woden” was substituted for Mercury and the name Wōdnesdæg (“Woden's day”) was used instead. The counterpart of the Norse god Odin, Woden is the supreme god in Germanic mythology, and is commonly identified with Mercury, the Roman god of commerce and the messenger of the gods.
Thor’s Day
The Romans called Thursday diēs Jovis, meaning ”day of Jupiter” (“Jove” is another name for Jupiter, the supreme Roman god). Yet in Old English, this name became Thūres dæg, a name likely influenced by the Old Norse Thōrsdagr, meaning “Thor's day.” Thor is the Norse god of thunder and the sky, and he is commonly identified with Jupiter.
Freya’s Day... Or Frigg’s Day
The Latin name for Friday—diēs Veneris—invokes Venus, the Roman goddess of love and beauty. In Old English, Venus was replaced with a Norse goddess—but which one? The Old English name Frigedæg has been said to refer to both Freya and Frigg, perhaps because they are both are goddesses of love (like Venus). Either way, TFIF.
Saturn’s Day
“Saturday” is closely related to the Latin diēs Sāturnī, which literally means “Saturn's day,” referring to the Roman god of harvests and father of Jupiter. The Old English name Saternesdæg is a translation of the Latin name, and “Saturday” is not far removed from the Middle English word for this day: Saturdai.
