

Pure sciences and exact or mathematical sciences, including astronomy, mechanics and mathematical physics.
| Acronym | Sense | Language | Topics | 
|---|---|---|---|
| H | Hidrogen = H | Hydrogène | In French = H | Waterstof | In Afrikaans = H | هيدروجين | In Arabic = H | Hidróxenu | In Asturian = H | Hidrogen | In Azerbaijani = H | Wassastoff | In Austro-Bavarian = H | Вадарод | In Belarusian = H | Водород | In Bulgarian = H | হাইড্রোজেন | In Bengali = H | Hidrogen | In Breton = H | Vodonik | In Bosnian = H | Hidrogen | In Catalan = H | Idroheno | In Cebuano = H | Idrogenu | In Corsican = H | Vodík | In Czech = H | Водород | In Chuvash = H | Hydrogen | In Welsh = H | Brint | In Danish = H | Wasserstoff | In German = H | Υδρογόνο | In Greek = H | Hydrogen | In English = H | Hidrogeno | In Esperanto = H | Hidrógeno | In Spanish = H | Vesinik | In Estonian = H | Hidrogeno | In Basque = H | هیدروژن | In Persian = H | Vety | In Finnish = H | Hydrogen | In Faroese = H | Idrogjen | In Friulian = H | Hidrigin | In Irish = H | Haidreagain | In Scottish Gaelic = H | Hidróxeno | In Galician = H | હાઈડ્રોજન | In Gujarati = H | מימן | In Hebrew = H | हाइड्रोजन | In Hindi = H | Vodik | In Croatian = H | Idwojèn | In Haitian Creole = H | Hidrogén | In Hungarian = H | Ջրածին | In Armenian = H | Hydrogeno | In Interlingua = H | Hidrogen | In Indonesian = H | Hidrogeno | In Ido = H | Vetni | In Icelandic = H | Idrogeno | In Italian = H | 水素 | In Japanese = H | წყალბადი | In Georgian = H | អ៊ីដ្រូសែន | In Khmer (Cambodian) = H | ಜಲಜನಕ | In Kannada = H | 수소 | In Korean = H | Hîdrojen | In Kurdish = H | Hydrogenium | In Latin = H | Waasserstoff | In Letzeburgesh = H | Waterstof | In Limburgish = H | Idrògen | In Lombard = H | Idrojɛ́ní | In Lingala = H | Vandenilis | In Lithuanian = H | Ūdeņradis | In Latvian = H | Hauwai | In Māori = H | Водород | In Macedonian = H | ഹൈഡ്രജന് | In Malayalam = H | Устөрөгч | In Mongolian = H | हायड्रोजन | In Marathi = H | Āyōcoxqui | En Nahuatl = H | Waterstoff | In Low German = H | Waterstof | In Dutch = H | Hydrogen | In Nynorsk = H | Hydrogen | In Norwegian = H | Hidrogene | NOV = H | Idrogèn | In Occitan = H | Hiidrojen | In Pitcairn-Norfolk = H | Wodór | In Polish = H | Hidrogénio | In Portuguese = H | Yakuchaq | In Quechua = H | Hidrogen | In Romanian = H | Водород | In Russian = H | हाइड्रोजन | In Sanskrit = H | Idrògginu | In Sicilian = H | Vodik | In Serbo-Croatian = H | Vodík | In Slovak = H | Vodik | In Slovenian = H | Hidrogjeni | In Albanian = H | Водоник | In Serbian = H | Hidrogén | In Sundanese = H | Väte | In Swedish = H | Hidrojeni | In Swahili = H | ஹைட்ரஜன் | In Tamil = H | హైడ్రోజన్ | In Telugu = H | Ҳидроген | In Tajik = H | ไฮโดรเจน | In Thai = H | Idroheno | In Tagalog = H | Hidrojen | In Turkish = H | Водень | In Ukrainian = H | آبگر | In Urdu = H | Vodorod | In Uzbek = H | Hiđrô | In Vietnamese = H | Woaterstof | In Vlaams = H | Idrodjinne | In Walloon = H | 氢 | In Wu Chinese = H | היידראזשן | In Yiddisch = H | 氢 | In Chinese | In Malay | → Chemistry | 
| H | Āyōcoxqui = (look above) | En Nahuatl | → Chemistry | 
| H | Waterstoff = (look above) | In Low German | → Chemistry | 
| H | Waterstof = (look above) | In Dutch | → Chemistry | 
| H | Hydrogen = (look above) | In Nynorsk | → Chemistry | 
| H | Hydrogen = (look above) | In Norwegian | → Chemistry | 
| H | Hidrogene = (look above) | [NOV] | → Chemistry | 
| H | Idrogèn = (look above) | In Occitan | → Chemistry | 
| H | Hiidrojen = (look above) | In Pitcairn-Norfolk | → Chemistry | 
| H | Wodór = (look above) | In Polish | → Chemistry | 
| H | Hidrogénio = (look above) | In Portuguese | → Chemistry | 
| H | Yakuchaq = (look above) | In Quechua | → Chemistry | 
| H | Hidrogen = (look above) | In Romanian | → Chemistry | 
| H | Водород = (look above) | In Russian | → Chemistry | 
| H | हाइड्रोजन = (look above) | In Sanskrit | → Chemistry | 
| H | Idrògginu = (look above) | In Sicilian | → Chemistry | 
| H | Vodik = (look above) | In Serbo-Croatian | → Chemistry | 
| H | Vodík = (look above) | In Slovak | → Chemistry | 
| H | Vodik = (look above) | In Slovenian | → Chemistry | 
| H | Hidrogjeni = (look above) | In Albanian | → Chemistry | 
| H | Водоник = (look above) | In Serbian | → Chemistry | 
| H | Hidrogén = (look above) | In Sundanese | → Chemistry | 
| H | Väte = (look above) | In Swedish | → Chemistry | 
| H | Hidrojeni = (look above) | In Swahili | → Chemistry | 
| H | ஹைட்ரஜன் = (look above) | In Tamil | → Chemistry | 
| H | హైడ్రోజన్ = (look above) | In Telugu | → Chemistry | 
| H | Ҳидроген = (look above) | In Tajik | → Chemistry | 
| H | ไฮโดรเจน = (look above) | In Thai | → Chemistry | 
| H | Idroheno = (look above) | In Tagalog | → Chemistry | 
| H | Hidrojen = (look above) | In Turkish | → Chemistry | 
| H | Водень = (look above) | In Ukrainian | → Chemistry | 
| H | آبگر = (look above) | In Urdu | → Chemistry | 
| H | Vodorod = (look above) | In Uzbek | → Chemistry | 
| H | Hiđrô = (look above) | In Vietnamese | → Chemistry | 
| H | Woaterstof = (look above) | In Vlaams | → Chemistry | 
| H | Idrodjinne = (look above) | In Walloon | → Chemistry | 
| H | 氢 = (look above) | In Wu Chinese | → Chemistry | 
| H | היידראזשן = (look above) | In Yiddisch | → Chemistry | 
| H | 氢 = (look above) | In Chinese | → Chemistry | 
| H5N1 | Hämagglutinin 5 Neuraminidase 1 | In German | → Enzymes → Blood and circulatory system → Cardiology | 
| HAADF | High Angle Annular Dark Field | In English | → Physics | 
| HAAG | Handbook of Astronomy, Astrophysics and Geophysics | In English | → Serial publications, periodicals → Astronomy → Geophysics | 
| HACEK | Haemophilus, Actinobacillus, Cardiobacterium, Eikenella & Kingella | In Latin | → Microbiology → Infectious diseases | 
| HAD | Historical Astronomy Division | In English | → Astronomy → History | 
| HALCA | Highly Advanced Laboratory for Communications and Astronomy | In English | → Astronautics → Telecommunications → Astronomy | 
| HalRe | Hale Observatories Reprints | In English | → Serial publications, periodicals → Astronomy | 
| HamS | Hamburger Sternwarte Sonderdrucke | In German | → Serial publications, periodicals → Astronomy | 
| HAP | High-Speed Arithmetic Processor | In English | → Computer hardware → Mathematics | 
| HarAC | Harvard College Observatory Announcement Card | In English | → Serial publications, periodicals → Astronomy | 
| HarAR | Harvard College Observatory Annual Report | In English | → Serial publications, periodicals → Astronomy | 
| HarCi | Harvard College Observatory Circular | In English | → Serial publications, periodicals → Astronomy | 
| HARIMAU | Hydrometeorological Array for ISV-Monsoon Automonitoring (www.jamstec.go.jp/iorgc/harimau/) | In English | → Meteorology, climatology → Hydrology | 
| HarPa | Harvard College Observatory Papers | In English | → Serial publications, periodicals → Astronomy | 
| HarRe | Harvard College Observatory Reprints | In English | → Serial publications, periodicals → Astronomy | 
| HarZi | Harthaer Beobachtungs-Zirkular | In German | → Serial publications, periodicals → Astronomy | 
| HBB | Horizons in Biochemistry and Biophysics | In English | → Serial publications, periodicals → Biochemistry, biophysics | 
| HBGP | Honigbienen-Genomprojekt (www.hgsc.bcm.tmc.edu/projects/honeybee/) = HBGP | Honey Bee Genome Project | In English | In German | → Genetics | 
| HBGP | Honey Bee Genome Project (www.hgsc.bcm.tmc.edu/projects/honeybee/) = (look above) | In English | → Genetics | 
| hBGP | Human Biliary Glycoprotein | In German | → Proteins | 
| HBP | Handbook of Biological Physics | In English | → Serial publications, periodicals → Biochemistry, biophysics | 
| hCEA | Human Carcinoembryonic Antigen | In English | → Biological sciences | 
| HCFC | Hydrochlorofluorocarbone | In French | → Chemistry → Chemical technology | 
| HCM | Hémoglobine Corpusculaire Moyenne = MCH | Mean Corpuscular Haemoglobin | In English | In French | → Diagnostics → Blood and circulatory system → Proteins | 
| HCST | Haut Conseil de la Science et de la Technologie | In French | → Engineering, technology | 
| HCT | Hot Cell Technology | In English | → Nuclear, atomic, and molecular physics → 54458 → Nuclear technology | 
| HDA | Handbuch der Astrophysik | In German | → Serial publications, periodicals → Astronomy | 
| HDAC | Histone deacetylase | In English | → Genetics → Enzymes | 
| HDL | High Density Lipoprotein | In English | → Proteins | 
| HDP | Handbuch der Physik | In German | → Serial publications, periodicals → Physics | 
| He | Helium = He | Hélium | In French = He | Helium | In German = He | Гелій | In Belarusian = He | Хелий | In Bulgarian = He | Heli | In Catalan = He | Helijum | In Czech = He | Eliu | In Corsican = He | হিলিয়াম | In Bengali = He | Heliwm | In Welsh = He | Ήλιο | In Greek = He | Helio | In Spanish = He | Heliumo | In Esperanto = He | هيليوم | In Arabic = He | Heelium | In Estonian = He | هلیوم | In Persian = He | הליום | In Hebrew = He | હીલિયમ | In Gujarati = He | Eli | In Friulian = He | Héiliam | In Irish = He | हीलियम | In Hindi = He | Elyòm | In Haitian Creole = He | Հելիում | In Armenian = He | Helín | In Icelandic = He | ヘリウム | In Japanese = He | ჰელიუმი | In Georgian = He | 헬륨 | In Korean = He | Hêlyûm | In Kurdish = He | Haumāmā | In Māori = He | Хелиум | In Macedonian = He | Eliyúmu | In Lingala = He | Éli | In Lombard = He | ഹീലിയം | In Malayalam = He | हेलियम | In Marathi = He | Хелијум | In Serbian = He | Гелий | In Russian = He | Heliu | In Romanian = He | Tōnatiuyoh | En Nahuatl = He | Ilyu | In Quechua = He | ஹீலியம் | In Tamil = He | Гелій | In Ukrainian = He | 氦 | In Chinese = He | Geliy | In Uzbek = He | ฮีเลียม | In Thai | In English | → Chemistry | 
| He | Hélium = (look above) | In French | → Chemistry | 
| He | Helium = (look above) | In German | → Chemistry | 
| He | Гелій = (look above) | In Belarusian | → Chemistry | 
| He | Хелий = (look above) | In Bulgarian | → Chemistry | 
| He | Heli = (look above) | In Catalan | → Chemistry | 
| He | Helijum = (look above) | In Czech | → Chemistry | 
| He | Eliu = (look above) | In Corsican | → Chemistry | 
| He | হিলিয়াম = (look above) | In Bengali | → Chemistry | 
| He | Heliwm = (look above) | In Welsh | → Chemistry | 
| He | Ήλιο = (look above) | In Greek | → Chemistry | 
| He | Helio = (look above) | In Spanish | → Chemistry | 
| He | Heliumo = (look above) | In Esperanto | → Chemistry | 
| He | هيليوم = (look above) | In Arabic | → Chemistry | 
| He | Heelium = (look above) | In Estonian | → Chemistry | 
| He | هلیوم = (look above) | In Persian | → Chemistry | 
| He | הליום = (look above) | In Hebrew | → Chemistry | 
| He | હીલિયમ = (look above) | In Gujarati | → Chemistry | 
| He | Eli = (look above) | In Friulian | → Chemistry | 
| He | Héiliam = (look above) | In Irish | → Chemistry | 
| He | हीलियम = (look above) | In Hindi | → Chemistry | 
| He | Elyòm = (look above) | In Haitian Creole | → Chemistry | 
| He | Հելիում = (look above) | In Armenian | → Chemistry | 
| He | Helín = (look above) | In Icelandic | → Chemistry | 
| He | ヘリウム = (look above) | In Japanese | → Chemistry | 
| He | ჰელიუმი = (look above) | In Georgian | → Chemistry | 
| He | 헬륨 = (look above) | In Korean | → Chemistry | 
| He | Hêlyûm = (look above) | In Kurdish | → Chemistry | 
| He | Haumāmā = (look above) | In Māori | → Chemistry | 
| He | Хелиум = (look above) | In Macedonian | → Chemistry | 
| He | Eliyúmu = (look above) | In Lingala | → Chemistry | 
| He | Éli = (look above) | In Lombard | → Chemistry | 
| He | ഹീലിയം = (look above) | In Malayalam | → Chemistry | 
| He | हेलियम = (look above) | In Marathi | → Chemistry | 
| He | Хелијум = (look above) | In Serbian | → Chemistry | 
| He | Гелий = (look above) | In Russian | → Chemistry | 
| He | Heliu = (look above) | In Romanian | → Chemistry | 
| He | Tōnatiuyoh = (look above) | En Nahuatl | → Chemistry | 
| He | Ilyu = (look above) | In Quechua | → Chemistry | 
| He | ஹீலியம் = (look above) | In Tamil | → Chemistry | 
| He | Гелій = (look above) | In Ukrainian | → Chemistry | 
| He | 氦 = (look above) | In Chinese | → Chemistry | 
| He | Geliy = (look above) | In Uzbek | → Chemistry | 
| He | ฮีเลียม = (look above) | In Thai | → Chemistry | 
| HEAD | High Energy Astrophysics Division (http://https://head.aas.org/) | In English | → Organizations and associations → Astronomy → United States | 
| HEAO | High Energy Astronomical Observatory | In English | → Astronautics → Observatories | 
| HEAO | High Energy Astronomy Observatory | In English | → Astronautics → Astronomy | 
| HECh | High Energy Chemistry | In English | → Serial publications, periodicals → Chemistry | 
| HEGRA | High-Energy-Gamma-Ray Astronomy | In English | → Astronomy | 
| HEJ | Hungarian Electronic Journal of Sciences | In English | → Serial publications, periodicals → Hungary | 
| HEL | High-Energy Laser | In English | → Optics → Electromagnetism | 
| HELCUSS | High-Energy Laser Computerized Unmanned Space | In English | → Optics | 
| HELF | High-Energy Laser Fluence | In English | → Optics | 
| HELLP | Hemolysis, Elevated Liver enzymes and Low Platelet count | In English | → Diagnostics → Blood and circulatory system → Pathology → Enzymes | 
| HELM | Hypertextual Electronic Library of Mathematics | In English | → Libraries → Data → Mathematics | 
| HelOB | Helwan Institute of Astronomy and Geophysics Bulletins | In English | → Serial publications, periodicals → Astronomy → Geophysics | 
| HELSTF | High Energy Laser Systems Test Facility | In English | → Optics | 
| HemD | Hemel en Dampkring | In Dutch | → Serial publications, periodicals → Astronomy | 
| HEO | High Earth Orbit | In English | → Astronomy → Astronautics | 
| HEO | High-Energy Orbit | In English | → Astronomy → Astronautics | 
| HEPNP | High Energy Physics and Nuclear Physics | In English | → Serial publications, periodicals → Nuclear, atomic, and molecular physics | 
| HER | Human Epidermal growth factor Receptor | In English | → Biochemistry, biophysics | 
| HER | Hydroxyethylrutoside | In English | → Biochemistry, biophysics | 
| HERV | Human Endogenous RetroVirus | In English | → Virology → Infectious diseases | 
| HESS | Hydrology and Earth System Sciences | In English | → Serial publications, periodicals → Hydrology | 
| HESS | High-Energy Squib Simulator | In English | → Computer simulation → Physics | 
| HESS | High Energy Stereoscopic System | In English | → Observatories | 
| HESSD | Hydrology and Earth System Sciences Discussions | In English | → Serial publications, periodicals → Hydrology | 
| HET | Hypothèse extraterrestre = ETH | Extraterrestrial hypothesis | In English | In French | |
| HETE | High Energy Transient Explorer | In English | → Astronautics → Astronomy | 
| HEW | Hindu Kush Environmental Watch | In English | → Environmental protection | 
| HF | Hydrogen Fluoride | In English | → Chemistry → Chemicals | 
| HF/DF | Hydrogen Fluoride/Deuterium Fluoride | In English | → Chemistry → Chemicals | 
| HFC | Heat Flow and Convection | In English | → Thermodynamics | 
| HFP | Hardened Focal Plane | In English | → Optics | 
| HgA1c | Hemoglobin A1c | In English | → Proteins → Blood and circulatory system | 
| HGc-Dt-E | Mercury-Cadmium-Telluride | In English | → Chemistry → Chemical technology | 
| HGE | Handbook of Geophysical Exploration | In English | → Serial publications, periodicals → Geophysics | 
| HGeo | History of Geophysics | In English | → Serial publications, periodicals → Geophysics → History | 
| HGF | Hepatocyte Growth Factor | In English | → Biochemistry, biophysics | 
| HGP | Human Genome Project | In English | → Genetics | 
| HGSC | Human Genome Sequencing Center | In English | → Genetics | 
| HGT | Human Gene Therapy | In English | → Serial publications, periodicals → Genetics | 
| HGVT | Horizontal Ground Vibration Test | In English | → Acoustics | 
| HH | Hedgehog | In English | → Proteins | 
| HHV | Human Herpesvirus | In English | → Virology → Infectious diseases | 
| HiA | Highlights of Astronomy | In English | → Serial publications, periodicals → Astronomy | 
| HiGEM | High Resolution Global Environmental Modelling (www.higem.nerc.ac.uk) | In English | → Computer simulation → Threats to the environment → Earth sciences | 
| HIR | Hologram Image Register | In English | → Libraries → Optics | 
| HIRIS | High Resolution Imaging Spectrometer | In English | → Physics → Analytical chemistry | 
| HIV | Human Immunodeficiency Virus = VIH | Virus de l'Immunodéficience Humaine | In French = VIH | Virus d'Inmunodeficencia Humana | In Asturian = VIH | Vírus da imunodeficiência humana | In Portuguese = VIDH | Virus Immunitarii Defectus Humanae | In Latin = ŽIV | Žmogaus Imunodeficito Virusas | In Lithuanian = ХИВ | Хумане имунодефицијенције | In Serbian = MIV | Menslike Immuniteitsgebreksvirus | In Afrikaans = HIV | Humani Imunodeficientni Virus | In Slovenian = ВИЧ | Вирус иммунодефицита человека | In Russian = GIB | Giza Immunoeskasiaren Birusa | In Basque = HIV | Humaan Immunodeficiëntie Virus | In Dutch | In English | → Virology → Immunology and allergy → Infectious diseases | 
| HIV | Humani Imunodeficientni Virus = VIH, VIDH, ŽIV, ХИВ, MIV, ВИЧ, GIB (look above) | In Slovenian | → Virology → Immunology and allergy → Infectious diseases | 
| HIV | Humaan Immunodeficiëntie Virus = VIH, VIDH, ŽIV, ХИВ, MIV, ВИЧ, GIB (look above) | In Dutch | → Virology → Immunology and allergy → Infectious diseases | 
| HLA | Human Leucocyte Antigen | In English | → Biochemistry, biophysics | 
| HMM | Hidden Markov Models | In English | → Statistics → Mathematics | 
| HMPV | Humanes Metapneumovirus | In German | → Virology → Infectious diseases | 
| HMR | Helgoland Marine Research | In English | → Serial publications, periodicals → 50146 → Hydrology | 
| HMT | Heat and Mass Transfer | In English | → Serial publications, periodicals → Thermodynamics | 
| HNMS | Hellenic National Meteorological Service | In English | → Meteorology, climatology → Greece | 
| HOA | Hydroxylamine-oxydoreductase | In English | → Enzymes | 
| HOBt | Hydroxybenzotriazole | In English | → Chemistry → Chemicals | 
| HOE | Holographic Optical Element | In English | → Optics | 
| HOLAB | Holographic Laboratory Brassboard | In English | → Optics | 
| HOLIVAR | Holocene Climate Variability | In English | → Meteorology, climatology | 
| HoMAI | Hologram Manufacturers Association of India | In English | → Associations → Optics | 
| HOME | Hawaii Ocean-Mixing Experiment | In English | → Marine research, oceanography | 
| HOMO | Highest Occupied Molecular Orbital | In English | → Chemistry | 
| HOPS | Holografisch-Optische Projektionsscheiben | In German | → Optics | 
| HOPS | Harvard Ocean Prediction System (http://mseas.mit.edu/archive/HOPS/) | In English | → Marine research, oceanography | 
| HPCA | Hot Plasma Composition Analyzer | In English | → Plasma physics → Astronautics → Astronomy | 
| HPCRE | Handbook on the Physics and Chemistry of Rare Earths | In English | → Serial publications, periodicals → Physics → Chemistry | 
| HPF | Highest Probable Frequency | In English | → Mathematics | 
| HPICS | Heat Pipe Instrumentation and Control System | In English | → Thermodynamics | 
| HPLC | High Performance Liquid Chromatography | In English | → Chromatography, mass spectrography | 
| HPlPh | Handbook of Plasma Physics | In English | → Serial publications, periodicals → Plasma physics | 
| HPLS | History and Philosophy of the Life Sciences | In English | → Philosophy, psychology → Biological sciences → Medicine → History | 
| HPOL | High-Power Optics Laboratory | In English | → Research institutes → Optics | 
| HPR | High Pressure Research | In English | → Serial publications, periodicals → Physics → Chemistry | 
| HPSL | High Performance Smart Lid | In English | → Biological sciences | 
| HR | Homologous Recombination | In English | → Genetics | 
| HR | Heat-Resistant | In English | → Thermodynamics | 
| HR&T | Heat Rejection and Transport | In English | → Thermodynamics | 
| HREELS | High Resolution Electron Energy Loss Spectroscopy | In English | → Physics | 
| HRSC | High Resolution Stereo Camera | In English | → Astronomy → Astronautics | 
| HRSMC | Holland Research School of Molecular Chemistry (www.hrsmc.nl) | In Dutch | → Research institutes → Biochemistry, biophysics → Netherlands | 
| HRSO | High-Resolution Solar Observatory | In English | → Observatories → Solar system | 
| HRTEM | High Resolution Transmission Electron Microscopy | In English | → Physics | 
| HS | History of Science | In English | → History | 
| HS | Heat Shield | In English | → Thermodynamics | 
| HS | Hydrogen Sulfide | In English | → Chemistry → Chemical technology | 
| HSA | Health Science Authority | In English | → Medicine → Biological sciences |