[MRtecno98]

Doesn't it mean "Moon's day"? From a quick google it seems it derives from the greek "Selēnēs hēmera", where "Selēnēs" is the gooddess of the moon and "Hēmera" is the personification of day(all of this is straight from google[1] btw, i know nothing about ethymology, only thing that sparked my interest is that in most romance languages the word for monday has a similar root to "moon")

[1]: https://www.etymonline.com/word/Monday

Edit: also wikipedia https://en.wikipedia.org/wiki/Monday

[jhbadger]

He said the Greek (modern, not ancient) name -- Δευτέρα (Deftéra), which has nothing to do with moons, but means "second day". Obviously this only makes sense in a Christian context which starts the week on Sunday. Monday is "first day" (星期一) in Chinese, for example.

[owl57]

Christian context is a bit fuzzy here. On one hand, Monday is called the same in Hebrew (יום שני [yom sheni] = "second day"). On the other hand, Russian "вторник" [vtornik] ≈ "second" is Tuesday, same in other Slavic languages.

[dragonwriter]

Judaism and Christianity both treat Sunday as the first day of the week, so that it is the same in Hebrew is unsurprising.