D Dalton, John Dating DBS Decibel Degree Democritus Density Desalination DGPS Dielectric Dielectric Constant Diesel Engine Differential Global Positioning System (DGPS) Diffraction Digital Digital-To-Analog Conversion Diode Direct Broadcast Satellite (DBS) Direct Current (DC) Dispatching Dispersion-Shifted Fiber (DSF) Distillation Distribution DNS Domain Name Domain Name Service (DNS) Doppler Effect Dry Air Dry Cell DS-0 DS-1 Dynamic Voltage Regulator Dynamic Voltage Restorer Dynamo