HDN

HDN may refer to

Medicine

• Hemolytic disease of the newborn, an alloimmune illness
• Hydronephrosis, hydrostatic dilation of the kidney

Places

• Harlesden station, England, station code
• Yampa Valley Airport, Colorado, US, IATA code

Other

• Hyperdimension Neptunia, a video game series
• Hydrodenitrogenation, an industrial chemical process
• Northern Haida language of North America, ISO 639-3 code
• Philippine Human Development Network
• Hdn., an abbreviation for the Greek grammarian Aelius Herodianus