Where does “nokturia” come from?

nokturia (Finnish) comes from English nocturia, from English -uria, from Latin -ūria, from Ancient Greek -ουρία, from Ancient Greek οὖρον, from Proto-Indo-European h₂wers- — to rain, drip; to rain, sprinkle.

nokturia (Finnish): nocturia frequent need to arise during the night in order to urinate