当時|とうじtouji[1]atamadaka (head-high)

1. noun, adverbat that time; in those days
   我々われわれはその当時とうじよく放課後ほうかごに野球やきゅうをしたものだった。↗

   We would play baseball after school in those days.

• Synonymその時そのときNeutralPoints to a specific moment, including one just mentioned, as in 「その時電話が鳴った」; 「当時」 usually covers a stretch of time in the past.
• Synonymその節そのせつFormalA formal, courteous set phrase for the earlier time you dealt with someone, as in 「その節はお世話になりました」; used in greetings, a politeness 「当時」 lacks.
• Synonymその折そのおりWrittenRather formal, for that time or occasion, as in 「その折はよろしく」; found mostly in letters and polite set phrases.
• Synonymその頃そのころNeutralCovers the period around that time, as in 「その頃は学生だった」; close to 「当時」 but more colloquial, with a reminiscent feel.
• Antonym現在げんざいNeutralMeans the present, the opposite end of the timeline from 「当時」, which points to the past.
• Antonym現代げんだいNeutralRefers to the present day or modern era, contrasting with the past era that 「当時」 points to.

Use 「当時」 to look back on a period in the past. For a specific moment say 「その時」, for the period around it 「その頃」 (colloquial, reminiscent), and in polite greetings about past dealings 「その節」. 「現在」 and 「現代」 are the present-day opposites.

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

1. その時とき。その頃ころ。
2. 現在げんざい、今日（こんにち）きょう。