“Bygone days” in Japanese
Short answer
Bygone days in Japanese is “過去” (kako). Full meaning: the past, bygone days; one's past (that one would prefer remained secret); past (tense), preterit, preterite.
Other ways to say “Bygone days” in Japanese
在りし日
arishihi past days, bygone days, days of yore, the olden days; while still alive, during one's lifetime
過ぎ来し方
sugikoshikata the past, bygone days (years, age, etc.); the course (route) one has come by, the direction one came from
過古
kako the past, bygone days; one's past (that one would prefer remained secret); past (tense), preterit, preterite
旧
kyuu old, former, ex-; the old, old things, old customs; old times, bygone days
舊
kyuu old, former, ex-; the old, old things, old customs; old times, bygone days
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