D'Alembert's paradox

D'Alembert's principle

Dacite

Dairy cattle production

Dairy machinery

Dalitz plot

Dallis grass

Dalton's law

Dam

Damping

Daphniphyllales

Dark current

Dark energy

The Dark Energy Survey and Camera

Dark matter

Darmstadtium

DARPP-32

Darwin's bark spider

Dasheen

Dasycladales

Data communications and networks

Data compression

Data mining

Data mining process

Data reduction

Data science

Data structure

Data warehouse

Data-mining and informatics approaches for environmental contaminants

Database management system

Dataflow systems

Date

Dating methods

Datolite

Dawn ion propulsion system

Dawn mission

Dawsoniidae

Day

De Broglie wavelength

De Haas-van Alphen effect

De-extinction

Dead reckoning

Death

Death receptor

Decapoda

Decarboxylative couplings

Decay heat

Decibel

Deciduous plant

Decision analysis

Decision support system

Decision theory

Decomposition potential

Decompression illness

Decontamination of radioactive materials

Deep Impact mission

Deep inelastic collisions

Deep seabed mining

Deep-marine sediments

Deep-sea annelid worms

Deep-sea fauna

Deep-sea trench

Deepest nematodes

Deer

Defense against killer asteroids

Definite composition, law of

Definitive evidence for new elements 113 and 115

Defoliant and desiccant

Deforestation

Degeneracy (quantum mechanics)

Degenerative neural diseases

Degree of freedom (mechanics)

Degree-day

Dehumidifier

Dehydrogenation

Delay line

Delayed neutron

Deliquescence

Delocalization

Delta

Delta electrons

Delta resonance

Demagnetization

Dementia

Demodulator

Demospongiae

Denali earthquake

Dendritic macromolecule

Dendrochronology

Dendrology

Dengue fever

Denisovans

Denotational semantics

Density

Density matrix

Dental anthropology

Dental caries

Dentistry

Dentition

Denudation