- Heterocysts
- Heterodimerization
- Heterodimers
- Heteroduplex
- Heteroduplex analysis
- Heterogametic sex
- Heterogeneity
- Heterogeneous catalysis
- Heterogeneous catalysts
- Heterogeneous condition
- Heterokaryons
- Heterologous
- Heterologous expression
- Heterolysis
- Heteromer
- Heteronuclear single quantum coherence
- Heterophile antibody
- Heterophile antibody test
- Heterophoria
- Heteroplasmy
- Heteroreceptor
- Heteroresistance
- Heterosis
- Heterosubtypic immunity
- Heterotaxy
- Heterotaxy syndrome
- Heterotetramer
- Heterotopia
- Heterotopic
- Heterotopic ossification
- Heterotopic pregnancy
- Heterotrimeric G proteins
- Heterotrophs
- Heterozygosity
- Heterozygote
- Heterozygote advantage
- Heuristics
- Hexachlorobenzene
- Hexachlorobutadiene
- Hexachlorocyclopentadiene
- Hexachloroethane
- Hexachlorophene
- Hexadecanal
- Hexagonal phase
- Hexahydroxydiphenic acid
- Hexamethonium
- Hexamethyldisilazane
- Hexamethyldisiloxane
- Hexamidine
- Hexaminolevulinate
- Hexanal
- Hexane
- Hexanol
- Hexaploidy
- Hexavalent chromium
- Hexokinase
- Hexon protein
- Hexosamine
- Hexosamines
- Hexosaminidase
- Hexose monophosphate shunt
- Hexoses
- Hexyl acetate
- Hey1
- Heyde's syndrome
- Hfq
- Hhex
- Hi-C
- Hiatal hernia
- Hiatus
- Hiatus hernia
- Hib vaccine
- Hibernating myocardium
- Hibernation
- Hibernoma
- Hibiscus
- Hibiscus tea
- Hiccups
- Hick's law
- Hickey
- Hickman line
- Hidden Markov models
- Hidradenitis
- Hidradenitis suppurativa
- Hidradenocarcinoma
- Hidradenoma
- Hidradenoma papilliferum
- Hidrocystoma
- Hierarchy of evidence
- Higenamine
- High altitude
- High altitude cerebral edema
- High anion gap metabolic acidosis
- High ankle sprain
- High arched palate
- High carbohydrate diet
- High cholesterol
- High density lipoprotein
- High density lipoprotein cholesterol
- High dependency unit
- High dimensional data
- High endothelial venules
- High fat diet
- High frequency jet ventilation
- High frequency oscillations
- High frequency ventilation
- High mobility group
- High output cardiac failure
- High production volume chemicals
- High reliability organization
- High resolution manometry
- High risk population
- High throughput screening
- High throughput sequencing
- High tibial osteotomy
- High vaginal swab
- High vocal center
- High-altitude cerebral edema
- High-altitude pulmonary edema
- High-content screening
- High-dose estrogen
- High-energy X-rays
- High-energy phosphate
- High-functioning autism
- High-grade lymphoma
- High-grade prostatic intraepithelial neoplasia
- High-grade serous carcinoma
- High-intensity focused ultrasound
- High-mobility group
- High-molecular-weight kininogen
- High-output heart failure
- High-performance thin-layer chromatography
- High-power field
- High-protein diet
- High-resolution computed tomography
- High-resolution manometry
- High-risk pregnancy
- High-stakes testing
- High-throughput screening
- Higher consciousness
- Higher-order statistics
- Highly active antiretroviral therapy
- Hikikomori
- Hildebrand solubility parameter
- Hilgenreiner's line
- Hill coefficient
- Hill's muscle model
- Hilum
- Himbacine
- Hinchey Classification