| Haemataulics | Study of movement of blood through blood vessels | 
        
      | Hagiology | Study of saints | 
        
      | Halieutics | Study of fishing | 
        
      | Hamartiology | Study of sin | 
        
      | Harmonics | Study of musical acoustics | 
        
      | Hedonics | Part of ethics or psychology dealing with pleasure | 
        
      | Helcology | Study of ulcers | 
        
      | Heliology | Science of the sun | 
        
      | Helioseismology | Study of sun's interior by observing its surface oscillations | 
        
      | Helminthology | Study of worms | 
        
      | Hematology | Study of blood | 
        
      | Heortology | Study of religious feasts | 
        
      | Hepatology | Study of liver | 
        
      | Heraldry | Study of coats of arms | 
        
      | Heresiology | Study of heresies | 
        
      | Herpetology | Study of reptiles and amphibians | 
        
      | Hierology | Science of sacred matters | 
        
      | Hippiatrics | Study of diseases of horses | 
        
      | Hippology | The study of horses | 
        
      | Histology | Study of the tissues of organisms | 
        
      | Histopathology | Study of changes in tissue due to disease | 
        
      | Historiography | Study of writing history | 
        
      | Historiology | Study of history | 
        
      | Homiletics | The art of preaching | 
        
      | Hoplology | The study of weapons | 
        
      | Horography | Art of constructing sundials or clocks | 
        
      | Horology | Science of time measurement | 
        
      | Horticulture | Study of gardening | 
        
      | Hydrobiology | Study of aquatic organisms | 
        
      | Hydrodynamics | Study of movement in liquids | 
        
      | Hydrogeology | Study of ground water | 
        
      | Hydrography | Study of investigating bodies of water | 
        
      | Hydrokinetics | Study of motion of fluids | 
        
      | Hydrology | Study of water resources | 
        
      | Hydrometeorology | Study of atmospheric moisture | 
        
      | Hydropathy | Study of treating diseases with water | 
        
      | Hyetology | Science of rainfall | 
        
      | Hygiastics | Science of health and hygiene | 
        
      | Hygienics | Study of sanitation; health | 
        
      | Hygiology | Hygienics; study of cleanliness | 
        
      | Hygrology | Study of humidity | 
        
      | Hygrometry | Science of humidity | 
        
      | Hymnography | Study of writing hymns | 
        
      | Hymnology | Study of hymns | 
        
      | Hypnology | Study of sleep; study of hypnosis | 
        
      | Hypsography | Science of measuring heights |