What is "katabasis"

n. A journey downwards: a journey downhill, a decrease of winds, a military retreat, a trip to the underworld; a trip from the interior of a country to the coast.

Katabasis or catabasis (from Greek κατὰ "down" and βαίνω "go") is a descent of some type, such as moving downhill, the sinking of the winds or sun, a military retreat, or a trip to the underworld or from the interior of a country down to the coast. The term has multiple related meanings in poetry, rhetoric, and modern psychology.