- decagon
- difference
- directivity
- dormitory
- diameter
- drove
- direction finder
- delay line
- drogue
- dehumanize
- dissever
- diffusion pump
- dependent variable
- double vision
- demesne
- dulcimer
- digenesis
- dermatosis
- dockyard
- digital clock
- digital watch
- depreciate
- dead reckoning
- decorum
- department
- defective
- demure
- decrepitation
- diverse
- drop hammer
- disavow
- demonolatry
- disafforest
- deforest
- disbelieve
- dispensary
- diverting
- deride
- dolor
- death rate
- dead language
- draftsman
- discharge lamp
- diopter
- disenchant
- distaste
- demimonde
- depressor muscle
- diacetylmorphine
- drying oil