古・往古|いにしえinishie[0]heiban (flat)

1. nounantiquity; ancient times; bygone days; former times

• Synonym往時おうじWrittenWritten register for bygone days or old times; 「古」(いにしえ) carries a nostalgic, poetic air and points to the remote past.
• Synonym既往きおうWrittenWritten word for what is already past, as in 「既往症」; 「古」 is poetic.
• Synonym往昔おうせきWrittenWritten word for ancient times, rarely used; 「古」 has a stronger literary flavor.
• Synonym往日おうじつWrittenWritten word for days gone by, rarely used; 「古」 stresses the remote past.
• Synonym旧時きゅうじWrittenWritten word for a former era, rarely used; 「古」 feels more nostalgic.
• Synonym昔時せきじWrittenWritten word for old times, rarely used; 「古」 is the more poetic of the two.
• Related過去かこNeutralNeutral, all-purpose word for the past, used objectively; 「古」 adds a nostalgic, poetic tone.
• Related昔むかしNeutralThe everyday word for 'long ago', by far the most common; 「古」 suggests a more distant past and a more literary tone.
• Related往年おうねんWrittenRefers to one's former years or heyday, as in 「往年の名選手」; 「古」 means remote antiquity.
• Related従前じゅうぜんWrittenMeans 'previously' or 'before', typical of official documents; 「古」 is poetic.
• Related昔年せきねんWrittenWritten word for past years, rarely used; 「古」 appears more often in poetry and prose.
• Related往代おうだいWrittenWritten word for a long-bygone age, rarely used.

For the remote past with a nostalgic, poetic feel, use 「いにしえ」, as in 「いにしえの都」. For everyday 'long ago' say 「昔」; for the objective past 「過去」; for one's former years 「往年」; in official writing 'previously' is 「従前」.

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

1. 遠とおい昔むかしの時代じだい。