Have you ever wondered what do the names of the days mean and how this differs in different languages? If so, this post is for you. We could say that many of the names they get in several languages come from astronomical objects or deities from the past.
In Latin, Monday was the day of the Moon: dies Lunae. Tuesday was dies Martis, the day of Mars. Then there was dies Mercurii (Mercury), dies Iovis (Jupiter), dies Veneris (Venus), dies Saturni (Saturn), and dies Solis (day of the Sun). Later on, with the arrival of Christianity, dies Solis was called dies Dominicus, the day of the Lord; and with Judaism dies Saturni changed to the Hebrew shabbath. The names of these planets were also the names of the Roman gods, so here we have both astronomical objects and deities. Romanic languages have very similar terms because they all come from Latin. Therefore, we have the Spanish names: Lunes, martes, miércoles, jueves, viernes, sábado and domingo; the French: lundi, mardi, mercredi, jeudi, vendredi, samedi and dimanche; the Italian: lunedì, martedì, mercoledì, giovedì, venerdì, sabato and Domenica. Portuguese is an exception for this rule, since its terms have no relation to the Latin names and follow a different structure. They start with Sunday, which is Domingo, following the other Romanic languages, but then Tuesday is segunda-feira (second day), and following this structure: terça-feira, quarta-feira, quinta-feira, sexta-feira, to finish the week with Sabado.
Germanic languages use variations of Proto-Germanic and Old Norse terms. The English Monday comes from mondæg, or monandæg, day of the moon. Tuesday, Tiwesdæg, was the day of Tiwaz, or Týr, a god of the Germanic pantheon which, curiously enough, is similar to Mars, the Roman god after which Tuesday is named. Wednesday, Wodnesdæg, was the day of Woden, who is better known as Odin. Thursday comes from Old Norse Þorsdagr, which was the day of Thor. Friday was also named after the goddess of love, like Venus, but in this case it was the Germanic version: Frig, and the Old English name was Frigedæg. Saturday and Sunday come from the same root that the Latin counterparts, Sæterdæg and Sunnandæg, meaning day of Saturn and day of the Sun respectively.
However, the North-Germanic languages do not call Saturday the day of Saturn, even if they share the same roots that the English names. Swedish, Norwegian, Danish and Icelandic share the origin of Monday, Tuesday, Wednesday, Thursday, Friday, and Sunday. But when it comes to Saturday they keep the Old Norse root, which has an interesting origin. The ancient Scandinavians had the habit of bathing, washing, and grooming themselves every Saturday. For this reason Saturday was called Laugardagur, day of bathing. From this word come the Swedish lördag, the Norwegian and Danish lørdag, and the Icelandic Laugardagur, which is the same word as in Old Norse because Icelandic has remained very similar as to how Scandinavians used to speak 1000 years ago.
Another trend to name the days is after the five elements, which is how they are in Japanese and Korean. In Japanese we have the symbols of the words Sun (日), Moon (月), Fire (火), Water (水), Tree/Wood (木), Gold/Metal (金), and Earth (土) in the Japanese days of the week: 月曜日 Getsuyōbi, 火曜日 Kayōbi, 水曜日 Suiyōbi, 木曜日 Mokuyōbi, 金曜日 Kin’yōbi, 土曜日 Doyōbi, and 日曜日 Nichiyōbi. Chinese used to have these same words (although with a different pronunciation) but nowadays they use a different system. They use the word 星期 xīngqī, which means “star period” and start counting: Monday is star period one (星期一), Tuesday is star period two (星期二) and so on, until Sunday, where we find again the symbol for “sun” or “day”: 星期日 xīngqīrì.
I think that it is very interesting to see how cultures that apparently have no relation do share the same roots in their words for the days, or that they named them after the same gods, even if adapting it to their own pantheon. There is, of course, more languages and linguistic families where there are for sure more content to analyze, but this is all for today. I hope you enjoyed this walk through etymology as much as I did.