Where does “Dodecaneso” come from?

Dodecaneso (Portuguese) comes from Latin Dodecanesus, from Ancient Greek Δωδεκάνησα, from Ancient Greek δώδεκα, from Proto-Indo-European *dwoΗdeḱm̥.

Ancestry of “Dodecaneso”, step by step

StepLanguageWordMeaning
1LatinDodecanesus—
2Ancient GreekΔωδεκάνησαtwelve islands
3Ancient Greekδώδεκαtwelve
4Proto-Indo-European*dwoΗdeḱm̥—
Every word from Proto-Indo-European *dwoΗdeḱm̥ →Every word from Ancient Greek δώδεκα →Every word from Ancient Greek Δωδεκάνησα →