- Demethylation
- Demeton-s-methyl
- Demineralized bone matrix
- Demister
- Demodulation
- Demographic
- Demographic profile
- Demography
- Demolition
- Demolition waste
- Demosaicing
- Demulsifiers
- Demurrage
- Denaturant
- Denaturation
- Dendrimers
- Dendritic
- Dendritic cells
- Dendritic spines
- Dendronized polymers
- Dengue fever
- Dengue virus
- Denier
- Denileukin diftitox
- Denim
- Denitrification
- Denitrifying bacteria
- Dennard scaling
- Denosumab
- Denotational semantics
- Dense breast tissue
- Dense connective tissue
- Dense granules
- Dense plasma focus
- Densely defined operator
- Densitometry
- Density altitude
- Density estimation
- Density gradient
- Density gradient centrifugation
- Density logging
- Density matrix
- Density of air
- Density of states
- Dental abscess
- Dental arch
- Dental caries
- Dental composite
- Dental erosion
- Dental fluorosis
- Dental implants
- Dental plaque
- Dental porcelain
- Dental prostheses
- Dental pulp stem cells
- Dental trauma
- Dentate gyrus
- Denticity
- Dentin
- Dentin hypersensitivity
- Dentinal tubules
- Denudation
- Denver Basin
- Deontic logic
- Deoxidization
- Deoxidizer
- Deoxyadenosine
- Deoxycholic acid
- Deoxycytidine
- Deoxygenation
- Deoxyguanosine
- Deoxyribonuclease
- Deoxyribonucleotides
- Deoxyribozymes
- Departmentalization
- Departure function
- Dependability
- Dependencies
- Dependency
- Dependency graph
- Dependent sources
- Dephasing
- Dephosphorylation
- Depleted uranium
- Depletion force
- Depletion gilding
- Depletion region
- Deployment
- Depolarization
- Depolarization ratio
- Depolarizer
- Depolymerization
- Deposit-refund system
- Deposition
- Depreciation
- Depressants
- Depressions
- Deprotonation
- Depsipeptide
- Depth filter
- Depth maps
- Depth of discharge
- Depth of field
- Depth of focus
- Depth perception
- Depth sounding
- Derailment
- Derating
- Derivative test
- Derivative-free optimization
- Derivatives
- Derivatization
- Derived set
- Derjaguin approximation
- Dermal equivalent
- Dermal fibroblasts
- Dermatan sulfate
- Dermatitis
- Dermatology
- Dermatomes
- Dermatophyte
- Dermatophytosis
- Dermatoscopy
- Dermis
- Derrick
- Desalination
- Desalter
- Desaturase
- Descaling agent
- Descartes' rule of signs
- Descending aorta
- Descending colon
- Descent
- Descloizite
- Describing function
- Description logic
- Descriptive geometry
- Descriptive research
- Descriptive statistics
- Descriptors
- Desensitization
- Desert rose
- Desert varnish
- Desertification
- Desiccants
- Desiccation
- Desiccation tolerance
- Desiccator
- Design basis accident
- Design brief