Digital Data Service 
Data Distribution Service 
Defense Dissemination System 
Direct Digital Synthesis 
Data Distribution System 
Dataphone Digital Service 
Doctor of Dental Surgery 
Domestic Data Service 
Direct Digital Synthesizer 
Digital Data Storage 
Digital Data System 
Data Display System 
Digital Data Services 
Deflection Detection System 
Data Description Specifications 
Data Dictionary System 
Data Dissemination System 
Detailed Design Specification 
Digital Dataphone Service 
Direct Digital Service 
Direct Digital Synthesizers 
Distributed Data System 
Doctor of Dental Science 
Documentation Distribution System 
Driver's Door Switch 
Dust Detector Subsystem 
Daily Data Set 
dapsone 
Data Disposition System 
Dataphone Digital Services