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