Where does “тетрадка” come from?

тетрадка (Russian) comes from Russian тетрадь, from Ancient Greek τετράδιον, from Ancient Greek τετράς, from Proto-Indo-European kʷetwóres, from Proto-Indo-European kʷe- — and.

Ancestry of “тетрадка”, step by step

Step	Language	Word	Meaning
1	Russian	тетрадь	exercise book, notebook
2	Ancient Greek	τετράδιον	quaternion of parchment
3	Ancient Greek	τετράς	the number four; tetrarchy; four-leaved pamphlet,...
4	Proto-Indo-European	kʷetwóres	four
5	Proto-Indo-European	kʷe-	and

Every word from Proto-Indo-European kʷe- →Every word from Proto-Indo-European kʷetwóres →Every word from Ancient Greek τετράς →