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 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 HIM – (i) His (or Her) Imperial Majesty HIMAD – (p) High to Medium Altitude Air Defence (see also H/MAD) 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