- Haab's striae
- Haber's rule
- Haber-Weiss reaction
- Haberman Feeder
- Habit cough
- Habit reversal training
- Habit-tic deformity
- Habits
- Habituation
- Haddon Matrix
- Hadhb
- HaeIII
- Haem carrier protein 1
- Haem peroxidase
- Haematology
- Haematopoiesis
- Haematopoietic stem cells
- Haematopoietic system
- Haematoxylin
- Haemodialysis
- Haemodynamic response
- Haemolytic uraemic syndrome
- Haemonchus contortus
- Haemophilia
- Haemophilia B
- Haemophilus ducreyi
- Haemophilus influenzae
- Haemophilus influenzae type b vaccine
- Haff disease
- Hafnia alvei
- Hafnium
- Hagen Poiseuille equation
- Hailey-Hailey disease
- Hair
- Hair analysis
- Hair cells
- Hair follicles
- Hair growth
- Hair loss
- Hair matrix
- Hair restoration
- Hair root
- Hair shaft
- Hair tourniquet
- Hair transplantation
- Hairpin ribozyme
- Hairy cell leukaemia
- Hairy cell leukemia
- Hairy leukoplakia
- Hairy tongue
- Halazepam
- Haldane effect
- Half and half nail
- Half life
- Half-cell
- Half-value layer
- Halfway houses
- Halichondrin
- Halides
- Halimeter
- Halite
- Halitosis
- Hallermann Streiff Syndrome
- Hallermann-Streiff syndrome
- Hallmarks of aging
- Hallucinations
- Hallucinogenic plants
- Hallucinogens
- Hallucinosis
- Hallux
- Hallux rigidus
- Hallux valgus
- Halo brace
- Halo effect
- Halo nevus
- Halo sign
- HaloTag
- Haloalkanes
- Halofantrine
- Halofuginone
- Halogenated hydrocarbons
- Halomonas
- Haloperidol
- Halorhodopsin
- Halothane
- Halotolerance
- Halstead-Reitan Neuropsychological Battery
- Hamamelis virginiana
- Hamartomas
- Hamate bone
- Hamilton Anxiety Rating Scale
- Hamilton Depression Rating Scale
- Hamiltonian
- Hamiltonian operator
- Hamman's sign
- Hammer toe
- Hammerhead ribozyme
- Hamstring
- Hamulus
- Hand