Final answer:
Poseidon is angry with Odysseus because he blinded Poseidon's son, Polyphemus, in Homer's epic poem, the Odyssey.
Step-by-step explanation:
Poseidon is angry with Odysseus because Odysseus blinded Poseidon's son, Polyphemus, who was a Cyclops. In Homer's epic poem, the Odyssey, Odysseus and his men land on the island of the Cyclopes and enter Polyphemus' cave. Odysseus, using his wit, blinds the Cyclops and manages to escape, but this act angers Poseidon, who is Polyphemus' father. As a result, Poseidon becomes anry with Odysseus and hinders his journey back home by causing him numerous hardships and obstacles at sea.
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