All articles starting with H
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Hornbeam
Hornbeam (Carpinus), a birch-family hardwood genus of about 19-40 Northern hemisphere species; European hornbeam (C. betulus) is a 25 m coppice and hedging tree of heavy lowland soils, with very hard wood used for cogs and mallets.
Hornbill
Hornbills (Bucerotidae, order Bucerotiformes) are Old World tropical birds, 16 genera and 64 species, with large casqued bills, sealed-cavity nesting, frugivory and seed dispersal, and casque-based thermoregulation; many species are threatened.
Hornbill Festival
The Hornbill Festival is a ten-day annual cultural festival held December 1 to 10 at Kisama near Kohima, Nagaland, where major Naga tribes present dances, music, and crafts.
Hornblende
Hornblende is a root-name group of dark green to black calcic amphibole minerals, documented by Abraham Gottlieb Werner in 1789, found in rocks such as granite, diorite, gabbro, and schist.
Hornblower (TV series)
Hornblower (1998–2003) is a British TV film series based on C.S. Forester's Horatio Hornblower novels, starring Ioan Gruffudd, aired on ITV and A&E, costing about £12 million and winning the 1999 Emmy for Outstanding Miniseries.
Hornbostel–Sachs
Hornbostel–Sachs (Systematik der Musikinstrumente, 1914) is the classification of musical instruments by sound production by Erich Moritz von Hornbostel and Curt Sachs: idiophones, membranophones, chordophones, aerophones, later electrophones, with decimal codes.
Hornby Railways
Hornby Railways: British model railway brand founded via Frank Hornby's 1920 clockwork trains under Meccano Ltd, later Tri-ang; known for UK 00 gauge (1:76, 16.5 mm) train sets, RailRoad ranges, TT:120, and HM7000 DCC control.
Horncastle
Horncastle: market town in East Lindsey, Lincolnshire, at the Bain-Waring confluence on the Roman walled site of Bannovallum; 13th-century market charter, famous August Horse Fair until 1948, antique shops.
Horndeski gravity
Horndeski gravity is the most general four-dimensional scalar-tensor theory of gravity with equations of motion no higher than second order, so it propagates no Ostrogradsky ghost.
Horned God
The Horned God is a modern pagan deity, a horned or antlered male figure of wild nature, sexuality, and rebirth worshipped alongside a Goddess in Wicca.
Horned lizard
Horned lizards (Phrynosoma, horny toads) are 17 species of spiny-headed North American lizards that eat harvester ants and squirt blood from eye sinuses to repel mammalian predators; the Texas horned lizard is threatened in Texas.
Horned owl
Horned owls, genus Bubo (horned owls, eagle-owls), large tufted Strigidae owls with 10 species; the Great Horned Owl (Bubo virginianus) spans the Americas, eats mostly mammals, and nests in other birds' old nests.
Horned screamer
Horned screamer (Anhima cornuta), also called anhuma or kamichi cornu, a large South American wetland bird of the Anhimidae with a 15 cm cartilaginous forehead horn, wing spurs, loud trumpeting calls, and IUCN Least Concern status.
Hornedjitef
Hornedjitef was a Theban priest of Amun, god's father and high-priest at Karnak in the early Ptolemaic period, buried at Asasif in Thebes in the 3rd century BC.
Horner–Wadsworth–Emmons reaction
The Horner–Wadsworth–Emmons reaction, also known as the Wittig–Horner reaction or HWE reaction, converts aldehydes and ketones into alkenes using phosphonate carbanions; developed in 1961 by Wadsworth and Emmons, it yields mainly E-alkenes and water-soluble phosphate byproducts.
Horner's method
Horner's method, also called Horner's rule or Horner's scheme, is an algorithm for evaluating a polynomial by rewriting it in nested form, using only n multiplications and n additions.
Horner's syndrome
Horner's syndrome (oculosympathetic paresis) is the triad of miosis, ptosis, and anhidrosis from disruption of the three-neuron sympathetic pathway to the eye; described by Horner in 1869, confirmed with apraclonidine or cocaine testing, and localized with hydroxyamphetamine.
Hornet
Hornet: large eusocial predatory wasps of the genus Vespa (Vespinae), also loosely applied to Dolichovespula maculata. Includes Vespa crabro, invasive Vespa velutina, and the eradicated US population of Vespa mandarinia.
Hornet (Hollow Knight)
Hornet is the fictional princess-protector of Hallownest from Team Cherry's Hollow Knight, a recurring boss voiced by Makoto Koji, and the protagonist of Hollow Knight: Silksong (September 4, 2025), set in Pharloom.
Hornet attacks and mass envenomation
Hornet attacks and mass envenomation is illness from many stings at once, driven by venom dose rather than allergy, most often from the Asian giant hornet.
Hornet predation on honey bees
Hornet predation on honey bees is the hunting of foragers and hive raids by hornets, chiefly the northern giant hornet, which can destroy a colony in hours.
Horng-Tzer Yau
Horng-Tzer Yau (姚鸿泽), born in Taiwan in 1959, is a Taiwanese-born mathematician and Merton Professor at Harvard known for proving universality of random matrix spectra with Erdős and Schlein.
Horniman Museum
The Horniman Museum and Gardens is a free museum in Forest Hill, south London, founded by tea trader Frederick Horniman; it opened in 1890 and 1901, holds about 350,000 objects, and returned 72 Benin bronzes to Nigeria.
Horns (film)
Horns (2013) is Alexandre Aja's supernatural horror thriller starring Daniel Radcliffe as Ig Perrish, based on Joe Hill's 2010 novel. After his girlfriend Merrin's murder, Ig grows horns that force confessions; premiered at TIFF 2013, released October 31, 2014.
Horns of Alexander
Horns of Alexander: ram's horns on coins and sculpture of Alexander the Great (356–323 BCE), symbolizing descent from Zeus-Ammon after the Siwa oracle; a symbolic attribute, not a physical feature, echoed by Arsinoe II and later art.
Horns of Moses
The horns of Moses are the two horn-like protrusions on Moses' head in Western Christian art, arising from the Vulgate's rendering of Exodus 34:29–35 and shaping imagery from eleventh-century manuscripts to Michelangelo.
Hornsby
Hornsby (Council of the Shire of Hornsby, Hornsby Shire) is a Sydney local government area established 6 March 1906, with about 154,000 residents across roughly 500 sq km, three wards, 10 councillors, and a TOD rezoning for 6,000+ homes.
Hornsdale Power Reserve
The Hornsdale Power Reserve (HPR) is a grid-scale energy storage facility in South Australia, operated by Neoen. Commissioned in 2017 and expanded in 2020, it utilized Tesla Powerpack lithium-ion technology.
Hornsea Wind Farm
Hornsea Wind Farm is a series of offshore wind farms in the North Sea off Yorkshire, England, developed by Danish company Ørsted within a licensing zone covering four projects.
Hornswoggle
Hornswoggle is the leprechaun wrestling character of Dylan Postl (born 1986, Oshkosh, Wisconsin), WWE 2006–2016, also known as Swoggle, last WWE Cruiserweight Champion (68 days, 2007) and the anonymous Raw General Manager.