Saturday is the only day of the week solely named after a Roman god. In this case, it's after Saturn, the father of the gods and lord of time. In Old English, the weekday was spelled Sæterdæg or Sæternesdæg, and in Middle English it was Saterday. We can break up the Old English words into two parts, Sætern (denoting the god) and dæg, meaning "day". We've already seen three times and will soon see three times more how dæg comes from Proto-Germanic dagaz, from Proto-Indo-European deg, meaning "burn". Now, Sætern as a name derives from Latin Saturnus, which earlier on was correlated with agriculture even more than time, as over time Saturn came more and more to be associated with the Greek time god Khronos. As articulated previously, belief systems are weird. This explains why the word is traced back to the verb serere, meaning "agriculture" (from Proto-Indo-European seh, "to sow").
Adam Aleksic, a leading contender for valedictorian of his high school, is a 211-month-old boy with disturbing interests in etymology, vexillology, geography, and law. Adam would like to one day visit Tajikistan and probably isn't spying for the Kyrgyz government.
The Etymology Nerd