HH may refer to:

Organizations

Happy Hippie Foundation The Happy Hippie Foundation is an American non-profit organization founded by entertainer Miley Cyrus on September 17, 2014, and officially launched to the public on May 5, 2015. The foundation focuses on youth homelessness (particularly among L ...

, a non-profit organization founded by Miley Cyrus *

Hartmann House Preparatory School Hartmann House Preparatory School (or Hartmann House, also referred to as HH) is an independent, preparatory, day school for boys in Harare, Zimbabwe. The school was founded in 1957 and named after Fr Hartmann SJ, a chaplain to the Pioneer Colu ...

, an independent preparatory school in Harare, Zimbabwe *

Heirs Holdings Heirs Holdings is a family-owned investment holding company headquartered in Lagos, Nigeria with investment interests in various sectors in Africa. History Heirs Holdings was founded in 2010 by Tony O. Elumelu, CON after his retirement in 2010 ...

, a Nigerian conglomerate with diversified interests *

Helly Hansen Helly Hansen (HH) is a Norwegian manufacturer and retailer of clothing and sports equipment and a subsidiary of the Canadian retail chain Canadian Tire. Currently headquartered in Oslo, it was previously headquartered in Moss, Norway from its fou ...

, a Norwegian brand specializing in clothing and gear for oceans and mountains *

Heywood Hill Heywood Hill is a bookshop at 10 Curzon Street in the Mayfair district of London. History The shop was opened by George Heywood Hill on 3 August 1936, with the help of Lady Anne Gathorne-Hardy, who would later become his wife. For the last thr ...

, a bookshop in London

Science and technology

* Hh, a signalling molecule in Drosophila named for the

Hedgehog signaling pathway The Hedgehog signaling pathway is a signaling pathway that transmits information to embryonic cells required for proper cell differentiation. Different parts of the embryo have different concentrations of hedgehog signaling proteins. The pathwa ...

hh blood group hh, or the Bombay blood group, is a rare blood type. This blood phenotype was first discovered in Bombay by Dr. Y. M. Bhende in 1952. It is mostly found in the Indian sub-continent (India, Bangladesh, Pakistan) and parts of Iran. Problems with ...

, a rare blood type *

Henderson–Hasselbalch equation In chemistry and biochemistry, the Henderson–Hasselbalch equation :\ce = \ceK_\ce + \log_ \left( \frac \right) relates the pH of a chemical solution of a weak acid to the numerical value of the acid dissociation constant, ''K''a, of acid and ...

, in biology and chemistry *

Herbig–Haro object Herbig–Haro (HH) objects are bright patches of nebula, nebulosity associated with newborn stars. They are formed when narrow jets of partially plasma (physics), ionised gas ejected by stars collide with nearby clouds of gas and dust at several ...

, in astronomy *

Hitchhiker Program The Hitchhiker Program (HH) was a NASA program established in 1984 and administered by the Goddard Space Flight Center (GSFC) and the Marshall Space Flight Center (MSFC). The program was designed to allow low-cost and quick reactive experiments t ...

, a NASA program established in 1984 * Hodgkin–Huxley model, an electrical model of neurons * Microsoft Compiled HTML Help (hh.exe) * Hereditary haemochromatosis

Transportation

* HH (Court Street Shuttle) a defunct line on the New York City Subway from 1936 to 1946 *

HH (Rockaway Shuttle) The Rockaway Park Shuttle is a New York City Subway shuttle train that operates in Queens. It connects with the train at Broad Channel station and is the latest iteration of the Rockaway Shuttle services that have been running on the Rockaway ...

, from 1962 to 1972 * HH Ferry route between Helsingborg, Sweden and Helsingør, Denmark * Air Hamburg, a German airline based in Hamburg (IATA code HH)

Other uses

hh (digraph) This is a list of digraphs used in various Latin alphabets. Capitalisation involves only the first letter (''ch'' becomes ''Ch'') unless otherwise stated (''ij'' becomes ''IJ''). Letters with diacritics are arranged in alphabetic order accordin ...

, in several languages * HH, a brassiere cup size * hh, an abbreviation for "

hands A hand is a prehensile, multi-fingered appendage located at the end of the forearm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each " ...

high" when referring to the height of a horse * HH, short for Hand-Held, a term in film production among camera staff *HH, the production code for the 1967 ''Doctor Who'' serial '' The Moonbase'' * Hakainde Hichilema, Zambian politician * Hamburg, Germany (ISO 3166-2 code DE-HH) and HH ("Hansestadt Hamburg"), vehicle licence plate prefix * Happy Hour, a period of time (not necessarily one hour) when bars and restaurants offer discounts on food and/or drinks * Heil Hitler, a chant prevalent in Nazi Germany and neo-Nazi groups * His

Highness Highness (abbreviation HH, oral address Your Highness) is a formal style used to address (in second person) or refer to (in third person) certain members of a reigning or formerly reigning dynasty. It is typically used with a possessive adjecti ...

, or Her Highness, a formal address *

His Holiness The title His Holiness (and the associated form of address Your Holiness) is an official title or style referring to the pope; this use can be traced back several hundred years. It is also an official title for Oriental Orthodox patriarchs or ...

, or Her Holiness, a formal address * Horrible Histories, media franchise *

Hulk Hogan Terry Eugene Bollea (; born August 11, 1953), better known by his ring name Hulk Hogan, is an American retired professional wrestler. He is widely regarded as the most recognized wrestling star worldwide and the most popular wrestler of the 19 ...

, American professional wrestler * Herbert Huncke, American Writer {{disambiguation