Dec
- Decade (log scale)
- Decatur Airport
- December
- Declan Donnelly
- Declination
- Delaware Electric Cooperative
- Department of Education and Communities (New South Wales)
- Department of Environment and Conservation (New South Wales)
- Department of Environment and Conservation (Western Australia)
- Derwent Entertainment Centre
- Deč
- Dheeraj and East Coast LLC
- Diethyl carbonate
- Diethylcarbamazine
- Digital Equipment Corporation
- Diplome d’Études Collegiales
- Direct energy conversion
- Disasters Emergency Committee
- Display Energy Certificate
- Distant Education Bureau
- Doncaster Education City
- Dubai Economic Council
- Francis E. Dec
- New York State Department of Environmental Conservation
- Oratorical Declamation