# 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)

## Contents

* Top
* H0–9 HA HB HC HD HE HF HG HH HI HJ HK HL HM HN HO HP HQ HR HS HT HU HV HW HX HY HZ
* h – (s) Hecto
* H – (s) Henry – Hydrogen

## HA

* 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

## HB

* 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

## HC

* 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

* 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

* 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

* 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

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

## HH

* 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

* hi – (s) Hindi language (ISO 639-1 code)
* HI – (s) Hawaii (postal symbol)
* HIC – Hierarchical Ingredient Code, a system of classifying drug ingredients
* 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

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

## HK

* 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

* 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

* 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 (disambiguation)

## HN

* 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

* 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

* 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

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

## HR

* 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

* 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

* 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

* 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

* 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

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

## HX

* 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

* 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

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