noun
declining fortunes; waning luck
Refers to a period of decreasing luck or prosperity, often used in a somewhat literary or formal context.
彼は衰運の時代を乗り越えて、再び成功を収めた。
He overcame a period of declining fortunes and achieved success again.
Compound of 衰 (decline, weaken) and 運 (luck, fortune). The exact historical derivation is uncertain, but the word follows a common Sino-Japanese pattern for abstract concepts.