Where does “ἐπικός” come from?

ἐπικός (Ancient Greek) comes from Ancient Greek ἔπος, from Ancient Greek ϝέπος, from Proto-Hellenic wékʷos, from Proto-Indo-European wékʷos, from Proto-Indo-European wekʷ- — to speak, to sound out.

ἐπικός (Ancient Greek): epic