Astronomical Names of the Day of the Week
Introduction
Ever since I was a child, I noticed a pattern in the Korean language. The name of each day in the week had a direct mapping to celestial bodies in our solar system. I brushed it off without much thought.
It wasn’t until I got a bit older that I noticed the English language also had a similar pattern. The name of each day in the week had some mapping to celestial bodies in our solar system! (Perhaps it should concern me I did not notice “Sunday” sooner).
One evening I sat down and decided to learn about the roots and origins of these names. I find it fascinating that you can see these patterns across so many languages - and the connections run deeper than one might think.
Names of the Days of the Week
Here we list the Korean names of the days, the Korean names of the celestial bodies, and the corresponding English names. The Korean names originate from China as we reference the Chinese characters of the elemental forces of nature such as Fire, Water, Wood, Metal and Earth (The Wuxing system).
Although the historical timeline is unclear, it is believed that the seven-day week system can be traced back to ancient Mesopotamia. The system then spread to the Greeks and Romans, which was passed along to China, and finally Korea [1].
Every planet name in Korean ends with the prefix 성(星) which originates from the Chinese character for “Star”. This aligns with our use of the English word “planet” which is derived from the Greek word ἀστήρ πλανήτης (astēr planētēs) meaning “wandering stars” [2].
| Name of Day | Celestial Body | English Name |
|---|---|---|
| 일(日)요일 | 일 (日) | Sun |
| 월(月)요일 | 월 (月) | Moon |
| 화(火)요일 | 화성 (火星) | Mars |
| 수(水)요일 | 수성 (水星) | Mercury |
| 목(木)요일 | 목성 (木星) | Jupiter |
| 금(金)요일 | 금성 (金星) | Venus |
| 토(土)요일 | 토성 (土星) | Saturn |
English is a Germanic language, and thus the names of the days are related to Nordic gods. However, the Germanic language itself adopted this system from the Romans, and substituted Roman gods with their own deities. We can also map the equivalent Greek gods [3].
| Name of Day | Norse God | Roman God | Greek God |
|---|---|---|---|
| Sunday | Sól | Sol | Helios |
| Monday | Máni | Luna | Selene |
| Tuesday | Týr | Mars | Ares |
| Wednesday | Odin | Mercury | Hermes |
| Thursday | Thor | Jupiter | Zeus |
| Friday | Frigg | Venus | Aphrodite |
| Saturday | - | Saturn | Cronus |
We can see a clear connection between the English names and old Nordic gods:
- Monday -> Máni’s day
- Tuesday -> Týr’s day
- Wednesday -> Odin’s day
- Thursday -> Thor’s day
- Friday -> Frigg’s day
Other Languages
As I was reading about this topic, I started thinking about the French and Spanish classes I used to take. (Un)surprisingly, we see familiar patterns here. Although you can see that Sunday and Saturday follow a different pattern. Sunday’s name comes from dies Dominicus (the Lord’s Day), and Saturday comes from the Sabbath.
| French Name of Day | Spanish Name of Day | Roman God |
|---|---|---|
| Dimanche | Domingo | - |
| Lundi | Lunes | Luna |
| Mardi | Martes | Mars |
| Mercredi | Miércoles | Mercury |
| Jeudi | Jueves | Jupiter |
| Vendredi | Viernes | Venus |
| Samedi | Sábado | - |
Conclusion
We probably take these names for granted and don’t give a second thought in our day-to-day (pun intended) lives, but it was fun to learn about this topic. To think that these names cross cultural, religious, and national boundaries across thousands of years is some food for thought.
Thanks for reading!
References
[1] https://www.cjvlang.com/Dow/dowjpn.html