How Did The Days Of The Week Get Their Names?

The names of days of the week in many languages are from the names of the seven celestial bodies (planets) in Hellenistic Astrology. These seven days also have the names of Roman gods and goddesses. Some other languages have names for days corresponding to regional cultural deities. 

This article explores the origin of the days of the week and the meaning of their names. We will explore the seven days of the week in other European languages, like Spanish, French, and Irish. The article also discusses some gods named after the days of the week.

Related read: How did the months of the year get their names?

Origin of the days of the week 

The origins of the days of the week can be traced back to Hellenistic astrology in Babylon. The Babylonians were the first to divide night and day into 12 hours. They divided each hour into 60 minutes and each minute into 60 seconds. They based this timing system on the movements of Earth around the sun and the Babylonian numbering system. Their weekly system had seven days.

They named the days of the week after the five planets of Hellenistic astrology. The planets are Saturn, Jupiter, Mars, Venus, Mercury, and the Moon. Eventually, the seven-day week spread to other cultures. 

The Egyptians used to have ten days a week, while the Romans had eight days. Even the Ancient Greeks adopted the Babylonian system of marking the passage of time in the 12th century. However, they changed the naming system and the number of days into a seven-day system. They named the days of the week after their gods. And the Romans also followed suit.

Since the Greeks and Romans had similar gods, the Roman Empire decided to name the days of the week after the Roman gods. Old English people, the Anglo Saxons with Germanic and Norse cultures, named the days of the week after the gods and goddesses in Norse mythology¹.

The meaning of the name of the days of the week

Monday 

Monday got its name from the moon. All languages and cultures called Monday the moon’s day, or celestial bodies that represented the moon. The Romans called the moon’s day dies lunae in Latin. They called Monday Luna's Day because of the Roman goddess of the moon, Luna. 

Norse people named Monday after the Norse God of the moon, Mani. Mani guided the moon across the sky by pulling the moon across the sky in a chariot. He follows his sister, goddess Sol, as she pulls the sun with her chariot. The old English referred to Monday as Mōnandæg. It also means the moon's day.

Related: Monday Quotes.

Tuesday  

Germanic and Norse cultures referred to Tuesday as Tīwesdæg, which means Tiw's Day. It is also spelt as Tiu. Tiw was a one-handed Norse god known for his single-handed combats. He is also the god of pledges. Old English also refers to Tuesday as Tiw's Day. 

Mars is the planet associated with Tuesday, and Romans named it after the Roman god of Mars. So they called it diēs Mārtis, the day of Mars. Most cultures named Tuesday after a god of warfare, but Tuesday is a peaceful day.

Related: Tuesday Quotes.

Wednesday 

Wednesday is associated with the Mercury planet. So, the Romans called it the day of Mercury. Apart from being a planet, Mercury is also a Roman God of commerce, eloquence, messages, and communication. Some also refer to him as the God of shopkeepers. 

Old English people referred to Wednesday as Wōdnesdæg. It means the day of the Germanic god, Woden. Until about the seventh century, the Anglo-Saxons praised Woden, the god of wisdom, war, poetry, and magic. He was the father of Thor, Balder, and Tiw. He's also known as the Norse god Odin or Wotan.

Related: Wednesday Quotes.

Thursday

As you can already tell, Thursday means Thor's Day. It also corresponds with the Roman god of thunder, Jupiter. In old English, it is Þūnresdæg, which means thunder's day.

Related: Thursday Quotes.

Friday 

The planet attached to Friday is Venus. Old English people called the day Frīgedæg, meaning Frige's Day.  She's a Germanic goddess of love. The Norse people had a name for the planet Venus. The name was Friggjarstjarna, meaning Frigg's Star. 

However, the Romans only refer to Friday with the name of the planet associated with it, Venus. They say diēs Veneris, "Day of Venus".

Related: Friday Quotes.

Saturday  

Saturday is the day of the week between Friday and Sunday. We refer to Saturday as Saturn's Day because it is the planet associated with the day. The people of Rome named the day after the Roman god Saturn. In old English, Saturday was Sæturnesdæg.

Related: Saturday Quotes.

Sunday 

Sunday is associated with the sun, so it's the sun's day. It originates from the Roman god of the sun, Sol. They call it diēs Solis. Old English people called it sunnandaeg, while Middle English called it sunnenday. Modern English now calls it Sunday.

Related: Sunday Quotes.

Days of the week in other languages 

Most languages, especially Romance languages, use Latin names for the days of the week. Romance languages are French, Spanish, Romanian, Italian, Catalan, Galician, etc. However, the sun’s day is different in these languages. Saturday became the sabbath day, while Sunday is the Lord’s Day.  

In Celtic languages, they maintained the Latin origin of the days of the week. However, they introduced separate terms of Norse origin for Wednesday, Thursday, and Friday. 

Here is a table summarizing the days of the week in French, Spanish, Italian, Galician, Irish and old Portuguese: 

The Roman Gods

Luna  

Luna is the Roman goddess of the moon. Roman art often depicts her as a crescent moon with two yoke chariots. She balances the delicate equilibrium of night and day in the skies. Luna is a symbol of femininity, awakening intuition, and renewal. Romans worshipped her during the new moon and full moon. 

Venus 

Venus is the Roman goddess of love, beauty, sex, desire, and fertility. Old Romans originally worshipped Venus as the goddess of fertility. However, some parts of Aphrodite, the Greek goddess of beauty and love, were attributed to Venus. Perspective Roman brides often offer gifts so that Venus can bless their marriage with fertility. 

Saturn 

Saturn was the god of time, agriculture, wealth, periodic renewal, and liberation. He is the son of the primordial earth mother, Terra. Romans usually celebrated him in December with lots of free speech, gift-giving, and feasting. 

Romans depicted him with the symbols synth, sickle, and veil. The synth represents an agricultural tool for harvesting, but it also means the deaths and bad omens in other cultures.

Sol

Ancient Rome had two Roman gods of the sun, Sol Indiges and Sol Invictus. They celebrated him on the 8th of August yearly. Sol had similar attributes to the Greek sun god, Helios. He represents vitality, fertility, and divine protection. Roman soldiers claimed Sol was their divine protection.

They believed the sun's vitality and radiance would guide them to victory. Sol's main temple was in the Circus Maximus.

Norse gods

Mani

Mani is a personification of the moon. Odin commissioned Mani to pull the chariots of the moon through the sky forever. Legend has it that Mani emerged with her brother Sol at the beginning of the cosmos. 

She rides her chariot with unfathomable speed because the wolves are chasing her. The wolves are Skoll, which represents Mockery, and Hati, which symbolizes Hatred. 

Tiw

Tiw, also known as Tyr, is a Norse god of warfare, treaties, and justice. In Norse myths, he is the son of Odin and half-brother to Thor, Baldr, and Heimdall. He was married to Zaia, the Norse goddess of harvest. 

Tiw is in charge of justice and war, and he punishes wrongdoers. Also, he is always present whenever warriors are signing treaties.

Thor

Thor is the Norse god of thunder, but he is also known as the god of the sky and agriculture. He is the son of Odin, the chief of gods, and the husband of Sif, the fertility goddess. Thor was the defender of the realm of gods and humans. These realms are Asgard and Midgard. 

Thor's weapon is his hammer, known as the Mjöllnir. He uses the hammer to harness and direct lightning to do his bidding. 

Naming System In Other Parts Of The World

Moving to another part of the world, Hindi introduced the seven-day week system into their culture. This concept was borrowed from Greek astrology in roughly the same period when Romans also received it.

In contrast, Arabic and Hebrew calendars adopted a more straightforward approach, adhering to an ordinal system. Here, the days are named sequentially as the first day, second day, etc.

Conclusion: How Did The Days Of The Week Get Their Names?

We have seven days in a week. These days are equally divided into 12 hours of night and day. Early Babylonians named the days of the week after the seven celestial bodies, while the Romans called them after their Roman gods. 

Always remember that Sunday is the sun's day, Monday is the moon's day, and Wednesday is Mercury's day. Thursday is Thor's day, Friday is Venus's day, and Saturday is for the Roman god, Saturn.