DDD

Template:Sister project DDD or Triple D may refer to:

Science and medicine

Defined daily dose, a World Health Organization statistical measure of drug use
Degenerative disc disease, a common disorder of the lower spine
Dense deposit disease, the preferred name for Membranoproliferative glomerulonephritis Type II
Dichlorodiphenyldichloroethane, a breakdown product of DDT
Dual pacing, dual sensing and dual response modes of a pacemaker
Depersonalization-derealization disorder, a psychiatric disorder involving feelings of oneself or the world being unreal, distant, or detached

Data Display Debugger or GNU DDD, a popular graphical user interface for command-line debuggers
Digital Divide Data, a social enterprise providing disadvantaged youths in Cambodia, Laos and Kenya with IT education and training
Direct distance dialing, a method for telephone subscribers to call long-distance numbers without operator assistance
DDD, the SPARS code for a CD that was recorded, mixed, and mastered digitally
Domain-driven design, a methodology and set of priorities for programming
Developer! Developer! Developer!, a series of community conferences for software developers
3D Systems (DDD), a company that makes devices for stereolithography or 3D printing

DDD, a bra size
Delta Delta Delta, a national collegiate sorority
Denali Destroyer Dolls, roller derby league based in Wasilla, Alaska
Dictionary of Deities and Demons in the Bible, an academic reference work
Destroy Dick December, an Internet challenge and follow-up to No Nut November
Die-deterioration doubling, a minting error on coins
Doe Triple-D, a make of tractor
Dhaalu Airport, Dhaalu Atoll, Maldives, IATA code DDD
Dongotono language of Southern Sudan, ISO 639-3 language code ddd
Doomsday device, a hypothetical construction — usually a weapon or weapons system — which could destroy all life on a planet, particularly Earth, or destroy the planet itself, bringing "doomsday", a term used for the end of planet Earth.