List of acronyms: H

This list contains acronyms, initialisms, and pseudo-blends  that begin with the letter H.

For the purposes of this list:

• acronym = an abbreviation pronounced as if it were a word, e.g., SARS = severe acute respiratory syndrome, pronounced to rhyme with cars
• initialism = an abbreviation pronounced wholly or partly using the names of its constituent letters, e.g., CD = compact disc, pronounced cee dee
• pseudo-blend = an abbreviation whose extra or omitted letters mean that it cannot stand as a true acronym, initialism, or portmanteau (a word formed by combining two or more words).

(a) = acronym, e.g.: SARS – (a) severe acute respiratory syndrome

(i) = initialism, e.g.: CD – (i) compact disc

(p) = pseudo-blend, e.g.: UNIFEM – (p) United Nations Development Fund for Women

(s) = symbol (none of the above, representing and pronounced as something else; for example: MHz – megahertz)

Some terms are spoken as either acronym or initialism, e.g., VoIP, pronounced both as voyp and V-O-I-P.

(Main list of acronyms)

• h – (s) Hecto
• H – (s) Henry – Hydrogen

• ha – (s) Hausa language (ISO 639-1 code) – Hectare
• HA – (s) Haiti (FIPS 10-4 country code) – (i) High Availability
• HAARP – (a) High Frequency Active Auroral Research Program
• HAART – (a) Highly Active Anti-Retroviral Therapy
• HAI – (i) Human Awareness Institute
• HAL – (i) Hardware Abstraction Layer
• HALO –
  • (a) Habitation and Logistics Outpost (of the planned Lunar Gateway space station)
  • High Altitude Low Opening (parachute jump)
• HALT
  • (a) Highly Accelerated Life Test
  • (a) Hungry Angry Lonely Tired
• HAMR – (a) Heat-assisted magnetic recording
• HAN - (s) IATA code for Noi Bai International Airport
• HANS – (a) Head And Neck Support (device used in many race cars)
• HARM – (a) High-speed Anti-Radiation Missile
• hat – (s) Haitian Creole language (ISO 639-2 code)
• HAT – (i/a) Highest Astronomical Tide (nautical charts) – (a) Hungarian Automated Telescope
• hau – (s) Hausa language (ISO 639-2 code)
• HAW – (i) Heavy Antitank Weapon
• HAWK – (a) Homing All the Way Killer (air defence system)
• HAZ – (i) Heat-Affected Zone
• HAZMAT – (p) Hazardous Materials

• HBCD – (p) HexaBromoCycloDodecane
• HBCI – (i) Home Banking Computer Interface
• HBCU – (i) Historically black colleges and universities (U.S.)
• HBO – (i) Home Box Office
• HBR – (i) Harvard Business Review
• HBT – (i) Heterojunction Bipolar Transistor
• HBV – (i) Hepatitis B Virus

• h.c. – (i) honoris causa (Latin, "for the sake of honor")
• HCAL — (p) Homogeneous calorimeter
• HCCI – (i) Homogeneous Charge Compression Ignition
• HCF – (i) Highest Common Factor
• HCI – (i) Human–Computer Interaction/Interface
• HCPCS – (i) Health Care Procedure Coding System
• HCSC – (i) Higher Command and Staff Course
• HCT – (i) Higher Colleges of Technology, tertiary education institution in the United Arab Emirates (UAE)

• HD
  • (i) Henry Draper (star catalogue)
  • Hull-Down (armored vehicle target, as opposed to Fully Exposed)
  • High Definition
  • Huntington's Disease
• HDD
  • (i) Hard Disk Drive
  • High-Density Disk
• HDL – (i) High-Density Lipoprotein
• HDM – (i) Human Decision-Making
• HDMI – High-Definition Multimedia Interface
• HDR
  • (i) Hard disk recorder
  • Henningson, Durham & Richardson (founders of the engineering and construction firm now known by their initials)
  • High dynamic range, a term used in both digital imaging and 3D rendering
  • Hot Dry Rock (experimental geothermal technology)
  • Human Development Report (UN publication)
• HDRA – (i) Henry Doubleday Research Association
• HDTV – (p) High-definition television

• he – (s) Hebrew language (ISO 639-1 code)
• He – (s) Helium
• HE – (a) High Explosive
• HEAT – (a) High-Explosive Anti-Tank (ammunition)
• heb – (s) Hebrew language (ISO 639-2 code)
• HEBA – (p) Hellenic Basketball Clubs Association
• HEER – (a) High-Explosive Extended Range (ammunition)
• HEIC – (i) Honourable East India Company
• HELOC – (a) Home equity line of credit
• HEMP – (a) High-Altitude Electromagnetic Pulse
• HEO
  • (a) High Earth orbit
  • (a) Highly elliptical orbit
• HEOSS – (a) High Earth Orbit Space Surveillance
• HEP – (i) High-Explosive Plastic (ammunition)
• HEPA – (a/i) High-Efficiency Particulate Air (filter)
• her – (s) Herero language (ISO 639-2 code)
• HESH – (a) High-Explosive, Squash-Head (ammunition)
• HESV – (i) Heavy Engineering Support Vehicle
• HETT – (a) Heavy Equipment Transporting Truck / Heavy Equipment Truck Tractor
• HEU – (i) Highly Enriched Uranium
• HEV
  • Hybrid Electric Vehicle (non-rechargeable)
  • Hazadous EnVironment suit - outfit worn by Half-Life protagonist Gordon Freeman
• Hewitts – (a) Hills in England, Wales and Ireland over Two Thousand feet (with topographic prominence of at least 30 m)

• Hf – (s) Hafnium
• HF – (i) High Frequency
• HFAC – (p) Human Factors ("aytchfak")
• HFE – (i) Human Fertilisation and Embryology (UK Act)
• HFE – (s) The common-emitter current gain in a BJT transistor (also represented by βF). See: BJT
• HFEA – (i) Human Fertilisation and Embryology Authority (UK)

• Hg – (i) Mercury (Latin Hydrargyrum)
• HGC – (i) UK Human Genetics Commission
• HGF – (i) Human Growth Factor
• HGTV – (i) Home & Garden Television

• HHD – (p) humanitatum doctor (Latin, "doctor of humanities")
• HHB – Ha Ha Bonk – The noise made when you laugh your head off. Used instead of LOL...
• HHS – (i) (U.S. Department of) Health and Human Services

• hi – (s) Hindi language (ISO 639-1 code)
• HI – (s) Hawaii (postal symbol)
• HIC – Hierarchical Ingredient Code, a system of classifying drug ingredients [1]
• HIDACZ – (p) High-Density Airspace Control Zone ("high dak zed/zee")
• HIH – (i) His (or Her) Imperial Highness
• HIIT - (a) High-Intensity Interval Training
• HIM – (i) His (or Her) Imperial Majesty
• HIMAD – (p) High to Medium Altitude Air Defence (see also H/MAD)
• HIMARS - (a) HIgh Mobility Artillery Rocket System
• HIMEZ – (a) High Altitude Missile Engagement Zone
• HIMYM – How I Met Your Mother
• hin – (s) Hindi language (ISO 639-2 code)
• HIPAA – (i) U.S. Health Insurance Portability and Accountability Act
• Hipparcos – (p) HIgh Precision Parallax COllecting Satellite
• Hird – (a) Hurd of interfaces representing depth (cf. HURD)
• HiRISE – (p) High Resolution Imaging Science Experiment
• HIT – (a) Health Information Technology
• HIV – (i) Human Immunodeficiency Virus
• HIWT – (i) Hobart Institute of Welding Technology

• HJ – (i) hic jacet (Latin, "here lies")
• HJD – (i) Heliocentric Julian Day

• HK – (s) Hong Kong (ISO 3166 digram; FIPS 10-4 territory code)
• HKD – (s) Hong Kong dollar (ISO 4217 currency code)
• HKG –
  • (s) Hong Kong (ISO 3166 trigram)
  • Hong Kong International Airport (IATA code)
• HKMAO – (i) Hong Kong and Macau Affairs Office
• HKO – (i) Hong Kong Observatory
• HKS – (i) HyperKinetic Syndrome
• HKSAR – (i) Hong Kong Special Administrative Region of the People's Republic of China

• hL – (s) Hectolitre
• HL
  • (i) Holding Line
  • (i) Half-Life
• HLA – (i) High Level Architecture (simulation) – Human Leukocyte Antigen
• HLL – (i) High-Level Language
• HLN – (i) Headline News
• HLOS – (i) High Level Output Specification
• HLS – (i) hoc loco situs (Latin, "laid in this place")
• HLVW – (i) Heavy Logistics Vehicle, Wheeled

• HM
  • (s) Heard Island and McDonald Islands (ISO 3166 digram; FIPS 10-4 territory code)
  • (i) His Majesty / Her Majesty (title for certain monarchs)
• H/MAD – (p) High/Medium Altitude Air Defence ("aytchmad"; see also HIMAD)
• HMCE – (i) Her/His Majesty's Customs and Excise (former UK government department; succeeded by HM Revenue and Customs)
• HMCS
  • (i) Her/His Majesty's Canadian Ship
  • Her Majesty's Courts Service (former UK agency; succeeded by Her Majesty's Courts and Tribunals Service)
• HMD
  • (s) Heard and McDonald Islands (ISO 3166 trigram)
  • (i) Helmet-Mounted Display
• HMF – (p) HydroxyMethyl Furfural
• HMICFRS - (i) His/Her Majesty's Inspectorate of Constabularies and of Fire and Rescue Services (UK Government agency)
• HMM – (i) Hidden Markov model
• HMMWV – (i) High Mobility Multipurpose Wheeled Vehicle ("hum-vee"; "hummer")
• hmo – (s) Hiri Motu language (ISO 639-2 code)
• HMO – (i) Health maintenance organization
• HMO – (i) House in multiple occupation
• HMO – (i) Human milk oligosaccharide
• HMP – (i) Her Majesty's Prison
• HMRC – (i) Her/His Majesty's Revenue and Customs
• HMS - (i) Her/His Majesty's Ship (Royal Navy)
• HMSO – (i) Her Majesty's Stationery Office
• HMV – (i) His Master's Voice

• HN – (s) Honduras (ISO 3166 digram)
• HND
  • (s) Honduras (ISO 3166 trigram)
  • Tokyo Haneda Airport (IATA code)
• HNL
  • (s) Honduran lempira (ISO 4217 currency code)
  • Daniel K. Inouye International Airport (IATA code)

• ho – (s) Hiri Motu language (ISO 639-1 code)
• Ho – (s) Holmium
• HO – (s) Honduras (FIPS 10-4 country code)
• HOLLAND – (a) Hope Our Love Lasts And Never Dies
• HOMES – the Great Lakes; Huron, Ontario, Michigan, Erie, Superior
• HONY – Humans of New York, a photoblog.
• HOPI – (a) Hybrid Optical and Packet Infrastructure (see Internet2, Abilene Network)
• HoReCa – (a) Hotel, Restaurant and Catering
• HORIZON – (p) Hélicoptère d'observation radar et d'investigation sur zone (French, Zone Investigation and Radar Observation Helicopter)
• HOSTAC – (a) Helicopter Operations from Ships Other Than Aircraft Carriers
• HOT – (a) Highly Optimised Tolerance
• HOTAS – (a) Hands on throttle-and-stick
• HOTT or HotT – (i) Hordes of the Things (miniature fantasy wargaming rules; a play on The Lord of the Rings)
• HOV – (i) High Occupancy Vehicle

• hp – (s) horse power
• HP –
  • (i) Hewlett-Packard
  • Hindustan Petroleum
  • (s) Himachal Pradesh (Indian state code)
• HPA – (i) UK Health Protection Agency
• HPCL – (i) Hindustan Petroleum Corporation Limited
• HPGL or HP-GL – (i) Hewlett-Packard Graphics Language
• HPH - (s) IATA code for Cat Bi International Airport
• HP-IB – (i) Hewlett-Packard Instrument/Interface Bus (first implementation of GP-IB, later standardised and now known as IEEE-488)
• HP-IL – (i) Hewlett-Packard Interface Loop (serial bus used with some HP calculators and computers, notably the HP-41 and HP-71 series)
• HPLC – (i) High Performance Liquid Chromatography
• HPMOR – (i) Harry Potter and the Methods of Rationality (work of Harry Potter fan fiction)
• HPT – (i) High[er] Payoff Target
• HPV – (i) Human Papilloma Virus

• HQ –
  • (i) Headquarters
  • (s) Howland Island (FIPS 10-4 territory code)
• HQ – (i) High Quality
• HQDA – (i) Headquarters, Department of the Army

• hr – (s) Croatian language (ISO 639-1 code)
• HR
  • (s) Croatia (FIPS 10-4 country code; ISO 3166 digram – from the country's native name of Hrvatska)
  • (s) Haryana (Indian state code)
  • (i) Harvard Revised star catalogue
  • Human Resources
• HRBL – (i) High-level Representation of Behavior Language (original name of the Herbal language)
• HRD – (i) Human Resource Development
• HRED – (i) (U.S. Army Research Laboratory's) Human Research and Engineering Directorate (Aberdeen Proving Ground, Maryland)
• HRF – (i) High Readiness Forces
• HRH – (i) His (or Her) Royal Highness
• HRK – (s) Croatian kuna (ISO 4217 currency code)
• HRM – (i) His (or Her) Royal Majesty
• HRM – (i) Human Resource Management
• HRT – (i) Hormone Replacement Therapy
• hrv – (s) Croatian language (ISO 639-2 code)
• HRV
  • (s) Croatia (ISO 3166 trigram)
  • (i) High Resolution Visible

• Hs – (s) Hassium
• HSA – A health savings account available to taxpayers in the United States.
• HSBC – (i) The Hong Kong and Shanghai Banking Corporation
• HSC
  • (i) Higher School Certificate
  • (i) Helicopter Sea Combat, a type of U.S Navy aviation squadron
• HSM – (i) High School Musical
• HSMAD – (i) Human Science/Modeling and Analysis Data
• HSN – (i) Home Shopping Network
• HSPH – (i) Harvard School of Public Health
• HSS
  • (i) Health Service Support
  • (i) High-Speed Steel
• HSSI – (i) High-Speed Serial Interface
• HST – see entry
• HSV
  • (i) Herpes Simplex Virus
  • Hue Saturation Value (colour model)

• ht – (s) Haitian Creole language (ISO 639-1 code)
• HT
  • (s) Haiti (ISO 3166 digram)
  • (i) High Temperature
  • hoc tempore (Latin, "at this time")
  • hoc titulo (Latin, "under this title")
• HTA – (i) HyperText Application
• HTC
  • High Tech Computer Corporation, original name of the company now known simply as HTC
• HTFU – (a) Harden The F**k Up
• HTG – (s) Haitian gourde (ISO 4217 currency code)
• HTH – (a) Hope That Helps
• HTI – (s) Haiti (ISO 3166 trigram)
• HTML – (i) HyperText Markup Language
• HTS – (i) High-Temperature Superconducting wire
• HTTP – (i) HyperText Transfer Protocol

• hu- (s) Hungarian language (ISO 639-1 code)
• HU – (s) Hungary (ISO 3166 digram; FIPS 10-4 country code)
• HUD – (i/a) Head-Up Display – Housing and Urban Development
• HUF – (s) Hungarian forint (ISO 4217 currency code)
• HUHA – (a) Head up his/her ass (Marine salute; probably a backcronym)
• HUI - (s) IATA code for Hue's Phu Bai International Airport
• HUMINT – (p) Human Intelligence (military parlance)
• Hum-Vee – See HMMWV
• hun – (s) Hungarian language (ISO 639-2 code)
• HUN – (s) Hungary (ISO 3166 trigram)
• HURD – (a) Hird of Unix-Replacing Daemons (cf. Hird)
• HVU – (i) High Value Unit (military)

• HV – (s) Upper Volta (ISO 3166 digram; obsolete 1984)
• HVAC – (s) Heating, ventilation and air conditioning Used in architecture, business and marketing; refers to a building's entire system of heating, moving, or cooling air.
• HVAP – (i) High Velocity Armour Piercing (ammunition)
• HVHF – (i)High velocity human factors
• HVI - (i) High Value Individual
• HVM – (i) High Velocity Missile
• HVO – (s) Upper Volta (ISO 3166 trigram; obsolete 1984)
• HVP –
  • (i) HarborView Properties
  • High vacuum process
  • Hydrolyzed vegetable protein
  • High Velocity Protection
  • H.V.P. (rapper)
  • High Voltage Protection
  • High Vapor Pressure
  • High-Velocity Projectile
  • High-Video Pass
  • High-Velocity Particle
  • Hub Voice Processor
  • Human Variome Project
• HVT - (i) High-Value Target (US military terminology)

• HW – (p) Hardware – (i) High Water (nautical charts)
• HWM – (i) Hardware morphing (computer graphics rendering)

• HX –
  • (s) IATA code of Hong Kong Airlines
  • (s) Medical history
  • (s) Hydrogen halide
  • (s) Concept automobile by HUMMER
• HXB – (s) The glycoprotein Tenascian C

• hy – (s) Armenian language (ISO 639-1 code)
• hye – (s) Armenian language (ISO 639-2 code)
• HYP
  • (i) Halkın Yükselişi Partisi (Turkish: "People's Ascent Party"), a political party in Turkey
  • Harvard, Yale, Princeton (perennially at or near the top of American university rankings)
• HYS – (i) Harvard, Yale, Stanford (perennially named as the top three law schools in the U.S.)

• hz – (s) Herero language (ISO 639-1 code)
• Hz – (s) Hertz
• HZ – (s) Haze (METAR Code)