- Dihydrostreptomycin
- Dihydrotachysterol
- Dihydrotestosterone
- Dihydrotetrabenazine
- Dihydrouracil
- Dihydrouridine
- Dihydroxyacetone
- Dihydroxyanthraquinone
- Dihydroxylation
- Dihydroxyphenylacetic acid
- Dihydroxyphenylglycine
- Diimine
- Diisocyanates
- Diisopropyl ether
- Diisopropyltryptamine
- Diketopiperazine
- Dilaceration
- Dilatation
- Dilatation and curettage
- Dilated cardiomyopathy
- Dilated fundus examination
- Dilation and curettage
- Dilation and evacuation
- Dilators
- Dilazep
- Dill
- Dill oil
- Diloxanide
- Diloxanide furoate
- Diltiazem
- Dilute Russell's viper venom time
- Dilute solution
- Dilution assay
- Dilution cloning
- Dimebon
- Dimenhydrinate
- Dimercaprol
- Dimercaptosuccinic acid
- Dimerization
- Dimers
- Dimethoate
- Dimethyl ether
- Dimethyl fumarate
- Dimethyl sulfate
- Dimethyl sulfoxide
- Dimethyl trisulfide
- Dimethylallyl pyrophosphate
- Dimethylamphetamine
- Dimethylaniline
- Dimethylcurcumin
- Dimethyldioctadecylammonium bromide
- Dimethyldithiocarbamate
- Dimethylethanolamine
- Dimethylformamide
- Dimethylglycine
- Dimethylhydrazine
- Dimethylmercury
- Dimethylnitrosamine
- Dimethyltryptamine
- Dimethylurea
- Dimeticone
- Dimetindene
- Diminazene
- Diminazene aceturate
- Diminished responsibility
- Dimocarpus longan
- Dimorphic fungi
- Dimorphism
- Dimple sign
- Dinaciclib
- Dinitrobenzene
- Dinitrophenyl
- Dinucleotide
- Dinucleotide repeat
- Dio2
- Dio3
- Dioctyl sodium sulfosuccinate
- Diode lasers
- Diogenes syndrome
- Diol
- Dioleoyl-3-trimethylammonium propane
- Diosgenin
- Diosmectite
- Diosmin
- Dioxane
- Dioxin
- Dioxins and dioxin-like compounds
- Dioxolanes
- Dioxybenzone
- Dioxygenase
- Dip
- Dipalmitoylphosphatidylcholine
- Dipeptidase
- Dipeptidyl peptidase
- Dipeptidyl peptidase 4
- Dipeptidyl peptidase I
- Dipeptidyl peptidase IV
- Dipeptidyl peptidase-4
- Dipeptidyl peptidase-4 inhibitors
- Dipeptidyl-peptidase I
- Diphencyprone
- Diphenhydramine
- Diphenhydramine hydrochloride
- Diphenidine
- Diphenoxylate
- Diphenyl disulfide
- Diphenylamine
- Diphenylbutylpiperidine
- Diphenylcarbazone
- Diphenylcyclopropenone
- Diphosphate
- Diphthamide
- Diphtheria
- Diphtheria antitoxin
- Diphtheria toxin
- Diphtheria toxoid
- Diphtheria vaccine
- Diphyllobothriasis
- Diphyllobothrium
- Diphyllobothrium latum
- Dipicolinic acid
- Dipipanone
- Dipivefrine
- Diplegia
- Diplococcus
- Diploe
- Diploic veins
- Diploidy
- Diplophonia
- Diplopia
- Diplopterys cabrerana
- Dipolar coupling
- Dipole moment
- Dipotassium hydrogen phosphate
- Diprenorphine
- Dipropyltryptamine
- Dipsomania
- Diptericin
- Dipyridamole
- Diquat
- Dira
- Diradicals
- Direct Analysis in Real Time
- Direct DNA damage
- Direct agglutination test
- Direct fluorescent antibody
- Direct immunofluorescence
- Direct instruction
- Direct pathway
- Direct repeat