D9
- 9D (disambiguation)
- ATC code D09
- Albatros D.IX
- Bavarian D IX
- Bottineau Municipal Airport
- Caterpillar D9
- D-9 (video)
- D-IX
- D9 road (Croatia)
- D9-brane
- Delta-9-THC
- Denza D9
- Diensteinheit IX
- Digital 9
- Digital government
- District 9
- Dix (disambiguation)
- Donavia
- Dublin 9
- HMS D9
- HMS Imperial (D09)
- HMS Trumpeter (D09)
- IDF Caterpillar D9
- Jodel D9
- LNER Class D9
- List of African-American fraternities
- National Pan-Hellenic Council
- Volkspolizei