- decalcification
- demersal
- dentated
- denticle
- denticulate
- dermal
- dextral
- diapause
- dichotomy
- diffuse
- diffusion
- digestive system
- dimorphism
- diploid
- disjunct
- dispersal
- dissected
- dissection
- distal
- distribution
- diurnal
- diurnal vertical migration
- diverge
- dorsal
- dorsal lip
- dorsal ribs
- dorsal side
- dorsum
- Dryas
- DZTU