What makes The Odyssey an epic poem?

Odysseus was spurned by the gods due to his arrogance at the greek victory over Troy. He wandered and met monsters like Scylla and Charybdis, the Cyclops along the way. and temptresses like Circe and Calypso. He went to the underworld to consult someone long dead. He was further refused a safe passage by Poseidon, and lost men and comrades until he was the only one left alive. He returned to Ithaca learning that his wife was the object of pursuit of many randy suitors, that his palace was made a drunken place by those who believed him dead. These suitors all met a tragic ending when Odyssues finally revealed himself.