D3
- 3D (disambiguation)
- ATC code D03
- Albatros D.III
- Bavarian D III
- D-3 (video)
- D-brane
- D3 (Tenchi Muyo! Ryo-Ohki)
- D3 (film)
- D3 Publisher
- D3 motorway (Czech Republic)
- D3 motorway (Slovakia)
- D3 road (Croatia)
- D3-class motor torpedo boat
- DDD (disambiguation)
- DOCSIS 3
- Daallo Airlines
- Dedication 3
- Descent 3
- Dewoitine
- Dhoom 3
- Diablo III
- Digivice
- Dihedral group of order 6
- Dirt 3
- Disgaea 3
- Doom 3
- Dopamine receptor D3
- Driver 3
- Dublin 3
- Dunne D.3
- Fokker D.III
- Ford D3 platform
- GNR Class D3
- Great Southern and Western Railway
- HMS Icarus (D03)
- HMS Ranee (D03)
- Hexamethylcyclotrisiloxane
- Iodothyronine deiodinase
- King Dedede
- London Buses route D3
- Melanoma in situ
- Mercedes D.III
- Mieses Opening
- NCAA Division III
- Nikon D3
- Pennsylvania Railroad class D3
- Peugeot D3
- Pfalz D.III
- Phönix D.III
- Pick database
- Schütte-Lanz D.III
- Siemens-Schuckert D.III
- USL League One
- USS D-3 (SS-19)
- Vitamin D3
- Voiced palato-alveolar affricate