In French, there is no doubt from Monday to Friday:
| Lundi (Monday) | Lunae dies | Moon |
| Mardi (Tuesday) | Martis dies | March |
| Mercredi (Wednesday) | Mercurii dies | Mercury |
| Jeudi (Thursday) | Jovis dies | Jupiter |
| Vendredi (Friday) | Veneris dies | Venus |
But there are two exceptions: Saturday and Sunday.
| Samedi (Saturday) | Saturn | The Romans renamed sabbati dies, the Sabbath day, a sacred day for the Jews (sabado in Spanish, sabato in Italian). Saturday’s relationship to Saturn remained in English. |
| Dimanche (Sunday) | Sun | In 389, the Roman emperor Theodosius I replaced the day of the Sun with the “Day of the Lord” dies Dominicus (domingo in Spanish, domenica in Italian). But Sunday’s relationship to the Sun remained for the Anglo-Saxons (in English, Sunday; in German, Sonntag). |
On the contrary, in English the same gods (and/or planets) are not followed for certain days:
| Monday | Moon day | |
| Tuesday | Thiw’s day, god of war (≈ Mars) | |
| Wednesday | Woden, ancient English name for Odin (Wotan) | |
| Thursday | Thor’s day (Thor is the son of Odin) | |
| Friday | Frigga, goddess of love (≈ Venus) | |
| Saturday | Saturn’s day | |
| Sunday | Sunday, day of the Sun |
So, there are exceptions to the rule “every day has its own planet!”.