An odyssey is a long wandering journey full of incident. A personal odyssey, an odyssey across Asia, a two-year odyssey.
The wandering is essential: a long straight journey is not one. It comes from Homer's poem about Odysseus taking ten years to sail home from Troy, and the word implies that the traveller is trying to get somewhere and being prevented.
1nounodysseyA long wandering journey full of incident.
“Their trip home turned into an odyssey of cancelled flights, lost bags and night buses.”
odyssey is a journey.
From the Odyssey, Homer's poem about the ten-year homeward voyage of Odysseus.
Ancient Greek
Ὀδυσσεία — the story of Odysseus
English, today
odyssey
From Odyssey, from Ancient Greek Ὀδυσσεία (“the story of Odysseus”).
Etymology from Wiktionary, CC BY-SA