MDD may refer to:
- Major depressive disorder, a mental disorder involving persistent low mood, low self-esteem and loss of interest. It is also known as clinical depression.
- Mate-Demate Device, a specialized crane used to piggyback the Space Shuttle onto an airplane
- Mammal Diversity Database, online checklist of mammal species maintained by the American Society of Mammalogists
- Medical Devices Directive
- Mernda railway station, Melbourne
- Midland Airpark (IATA: MDD), a public use airport in Midland, Texas
- Mine detection dogs
- Ministry of Defence (Italy), known natively as Ministero della Difesa
- Mirrored Drive Door, a case design for the Power Mac G4
- Model-driven development, a software engineering discipline
- Movement for Direct Democracy, defunct Venezuelan political party.
This disambiguation page lists articles associated with the title MDD.If an internal link led you here, you may wish to change the link to point directly to the intended article. Category: