Days of the Week in French

Six of the seven French days of the week carry the names of Roman gods and planets. This is not a coincidence or a quirk of French - it is the Roman inheritance that ran through Latin into most Western European languages. The Romans named each day of the week after one of the seven classical planetary bodies they recognised: the Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn.

French kept five of those Roman planetary names intact: lundi (lune = Moon), mardi (Mars), mercredi (Mercury), jeudi (Jupiter/Jove), and vendredi (Venus). English kept fewer - only Saturday from Saturn - and replaced the rest with Norse equivalents. That is why Thursday is both jeudi (Jupiter's day) and Thor's day: Thor and Jupiter were considered to occupy the same divine role across cultures.

The two exceptions in French are samedi and dimanche. When Christianity became the official religion of the Roman Empire, Church authorities replaced dies Saturni (Saturn's day) with dies sabbati (Sabbath day), which became samedi. Similarly, dies Solis (Sun's day) became dies Dominicus (the Lord's day), which became dimanche. This is the opposite of English, where Saturday and Sunday kept their pagan sun/saturn names.

Understanding this pattern is the single fastest way to memorise all seven days. Once you know that lundi = lunar = moon, mardi = martial = Mars, and jeudi = Jovian = Jupiter, you have built memory hooks that last. Read the full etymology story.