Septentrionate means "To point North", ultimately derived from Latin septentrio, "North". You have probably spotted the first element sept- is connected to the number seven. the second part, trio, is not to do with three, but apparently mean "plough ox". So what were these seven plough oxen? Well here they are:
A familiar constellation in the Norther sky, Ursa Major and often also called The Big Dipper/The Plough/Charles' Wain.
Latin also had Boreas, the North wind originally and I think borrowed from Greek (think Aurora Borealis). Modern Greek for North is still βορράς, voras, so it hasn't changed much, except that the letter beta has become a "b" sound to a "v" sound in Modern Greek.
I leaned that Septenrio was Latin for North from the excellent Words Unravelled podcast and YouTube channel, which also featured the surprising fact that Romance languages have names for North, South, East and West that are essentially the same as the English words, e.g French nord, sud, est, and ouest. This is as a result of borrowing, most likely from Old English into Old French and from there to the other languages, supplanting the names inherited from Latin.
It's not at all clear why this replacement happened. When I heard about it I assumed that the geographical closeness of France to England and of Spain, Portugal, Italy to France would have been a factor, but to my astonishment I found Romania shares the borrowing too, even though it's much further off. So it's a mystery.
And where did North come from anyway? Well not everyone agrees with it, but the strongest theory is that the word and its cognates in other Germanic languages come from a root that meant "left" (or perhaps "down" or both). Why would North be left? Because most ancient societies, would probably have been East oriented (literally), rather than North because that is where the Sun rises, and when we look East, where is North then?