Where does “octateuchus” come from?

octateuchus (Latin) comes from Ancient Greek ὀκτάτευχος [βίβλος], from Ancient Greek ὀκτα-, from Ancient Greek ὀκτώ — eight.

Ancestry of “octateuchus”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	ὀκτάτευχος [βίβλος]	containing eight books
2	Ancient Greek	ὀκτα-	eight
3	Ancient Greek	ὀκτώ	eight