既往|きおうkiou[0]heiban (flat)

1. no-adjectivethe past
   既往きおうは咎とがめず。↗

   Let bygones be bygones.

• Synonym過去かこNeutralThe everyday word for the past, with the broadest range. 「既往」 is the more written, formal term, confined mostly to medical 「既往歴」 and the idiom 「既往は咎めず」.
• Synonym昔むかしNeutralCommon in speech for days gone by, with a nostalgic feel; its time span is vaguer and stretches further back than 「既往」.
• Synonym古いにしえWrittenWritten word for remote antiquity with an elegant, archaic flavor, found mainly in poetry and prose; more distant than 「既往」.
• Synonym往年おうねんNeutralFormer years or someone's heyday, as in 「往年の名選手」 and 「往年の記録」; in everyday use, unlike the bookish 「既往」 or the rare 往- compounds.
• Synonym往時おうじWrittenWritten word for bygone days, often describing how something looked in its prime, as in 「往時の面影」.
• Synonym往昔おうせきWrittenWritten, archaic word for the distant past; very rare, and further back in time than 「既往」.
• Synonym往日おうじつWrittenWritten word for days gone by; very rare, with a nostalgic coloring.
• Synonym旧時きゅうじWrittenWritten word for old times; very rare — in normal use one says 「昔」.
• Synonym来し方きしかたWrittenThe path one has walked through life, with a reflective, wistful tone, as in 「来し方行く末」.
• Synonym昔年せきねんWrittenWritten, dated word for former years; very rare — in normal use one says 「昔」.
• Synonym昔時せきじWrittenWritten, dated word for a past period; very rare — in normal use one says 「往時」.
• Synonym過ぎ来し方すぎこしかたWrittenThe years one has come through, or the road one came by; carries a literary, lyrical flavor.
• Synonym往代おうだいWrittenWritten, dated word for the remote past; very rare — in normal use one says 「古代」.
• Related従来じゅうらいNeutralRefers to what has been so from before up to now, stressing continuity into the present, as in 「従来の方法」; it does not simply mean the past.
• Related従前じゅうぜんNeutralMeans before, or up to now; frequent in legal and official documents, as in 「従前どおり」.
• Antonym将来しょうらいNeutralAntonym: the future, the time ahead — the opposite of 「既往」, which points to what has already passed.
• Antonym未来みらいNeutralAntonym: the future, often the more distant future; the opposite of the past.

In everyday speech, use 「過去」 or 「昔」. For things already past in written language, use 「既往」, seen mostly in 「既往症」 and the idiom 「既往は咎めず」. When looking back over the course of one's life, use 「来し方」. 「往昔」, 「往日」, 「昔年」 and 「往代」 are rare literary words, while 「往年」 is fairly everyday; 「従来」 and 「従前」 stress continuity up to the present.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 過ぎ去すぎさった昔むかし。過去かこ。
2. 過去かこに罹患りかん、または経験けいけんしていること。既往歴きおうれき。