UDD

UDD may refer to:

Science and technology

 * Ultra-dense deuterium
 * Neutrons, which have quark configurations of udd, or up-down-down
 * Ultradisperse diamond, another name for Detonation nanodiamond
 * Urine-diversion dehydration toilet
 * User driven development

Others

 * Uniform Distribution of Deaths, an assumption used in building actuarial life tables
 * Bermuda Dunes Airport
 * UDD, the station code for the Uddingston railway station in Uddingston, Scotland
 * United Front for Democracy Against Dictatorship, a political movement in Thailand
 * Universidad del Desarrollo private university in Chile
 * UDD (band), a Filipino band