Dai-ichi
- 1st Air Fleet (Imperial Japanese Navy)
- 2011 Tōhoku earthquake and tsunami
- Dai (disambiguation)
- Dai Ichi Daihoumaru Ship case
- Dai-Ichi Kangyo Bank
- Dai-Ichi-dōri Station
- Dai-ichi (Go competition)
- Dai-ichi Life
- Daiichi Institute of Technology
- Daiichi Sankyo
- Fukushima Daiichi Nuclear Power Plant
- Ichiban (disambiguation)
- Japanese language
- Morioka First High School
- Ordinal number (linguistics)
- Radio Nikkei
- Shizuoka Daiichi Television