Encyclopedia

Hydrogen sulfide Hydrogen sulfide (hydrogen sulphide in British English), H2S, is a colorless, toxic, flammable gas that is responsible for the foul odor of rotten eggs and flatulence. It often results when bacteria break down organic matter in the absence of oxygen, such as in swamps, and sewers (alongside the process of anaerobic digestion).
Hydrogen vehicle A hydrogen vehicle is a vehicle, such as an automobile or aircraft, which uses hydrogen as its primary source of power for locomotion. These vehicles generally use the hydrogen in one of two methods: combustion or fuel-cell conversion.
Hydrogen-deuterium exchange Hydrogen-deuterium exchange (also called H-D or H/D exchange) is a chemical reaction in which a covalently bonded hydrogen atom is replaced by a deuterium atom, or vice versa. Usually the examined protons are the amides in the backbone of a protein.
Hydrogenated oil Hydrogenated oils are oils which have been hydrogenated through the addition of hydrogen in order to change their chemical properties. Vegetable oils and fats are hydrogenated by the food industry, typically to preserve their shelf life.
Hydrogenation Hydrogenation is a class of chemical reactions in which the net result is an addition of hydrogen (H2). The usual targets of hydrogenation are unsaturated organic compounds, such as alkenes, alkynes, ketones, nitriles, and imine.
Hydrogeology Hydrogeology (hydro- meaning water, and -geology meaning the study of rocks) is the part of hydrology that deals with the distribution and movement of groundwater in the soil and rocks of the Earth's crust, (commonly in aquifers). The term geohydrology is often used interchangeably.
Hydrographic survey Hydrographic survey is the process of gathering information about navigable waters for the purposes of safe navigation of vessels. It strictly applies to survey of any navigable waters, including lakes and rivers, but it is most commonly applied to marine navigation.
Hydrography of the Oak Ridges Moraine Preliminary research on the hydrology of the Oak Ridges Moraine began in the 1970s, but a broader research effort including the impact of urban development on the aquifer system and Great Lakes water quality was established in 1993. The research locus is the Geological Survey of Canada and the University of Toronto Groundwater Research Group, though other groups have made substantial contributions to this project.
Hydrogrossular Hydrogrossular, is a calcium aluminium garnet Ca3Al2(SiO4)3-x(OH)4x, with hydroxide (OH) partially replacing silica (SiO4).Gemological Institute of America, GIA Gem Reference Guide 1995, ISBN 0-87311-019-6 Hydrogrossular is found in massive crystal habit, sometimes grown in with idocrase.
Hydrochlorothiazide Hydrochlorothiazide (Apo-Hydro®, Aquazide H®, Dichlotride®, Hydrodiuril®, Microzide®, Oretic®), sometimes abbreviated HCT, HCTZ, or HZT is a popular diuretic drug that acts by inhibiting the kidney's ability to retain water. This reduces the volume of the blood, decreasing blood return to the heart and thus cardiac output and, by other mechanisms, is believed to lower peripheral vascular resistance.
Hydroida Hydroida is a cnidarian order which includes hydras, hydromedusae, and many marine attached hydroids, many of which grow up into large, elegantly branched forms. All the zooids of a colony are asexually produced from one parent zooid.
Hydroinformatics Hydroinformatics is a branch of Informatics which concentrates on the application of information and communications technologies (ICTs) in addressing the increasingly serious problems of the equitable and efficient use of water for many different purposes. Growing out of the earlier discipline of computational hydraulics, the numerical simulation of water flows and related processes remains a mainstay of hydroinformatics, which encourages a focus not only on the technology but on its application in a social context.
Hydrolock In automotive terminology, a hydrolock is the immobilization of an engine's pistons by a liquid (usually water, hence the prefix "hydro-"). Hydrolocking occurs when liquid fills a cylinder on the intake stroke and, due to the incompressibility of a liquid, makes the compression stroke impossible.
Hydrological transport model An hydrological transport model is a mathematical model used to simulate river or stream flow and calculate water quality parameters. These models generally came into use in the 1960s and 1970s when demand for numerical forecasting of water quality was driven by environmental legislation, and at a similar time widespread access to significant computer power became available.
Hydrology Hydrology (from Greek: Yδρoλoγια, Yδωρ+Λoγos, Hydrologia, the "study of water") is the study of the movement, distribution, and quality of water throughout the Earth, and thus addresses both the hydrologic cycle and water resources. A practitioner of hydrology is a hydrologist, working within the fields of either earth or environmental science, physical geography or civil and environmental engineering.
Hydrolyzed collagen (hydrolysate) Hydrolyzed collagen, HCP, (also known as purified gelatin and collagen hydrolysate) is collagen that has been enzymatically or chemically processed to make it more digestible and more easily absorbed by the body. HCP is often used by body builders because it is a relatively inexpensive protein source, although it is not the best source of protein.
Hydrolyzed protein Hydrolyzed Protein is protein that has been hydrolyzed or broken down into its component amino acids. While there are many means of achieving this, two of the most common are prolonged boiling in a strong acid or base or using an enzyme such as the pancreatic enzyme to stimulate the naturally-occurring hydrolytic process.
Hydrolyzed vegetable protein Hydrolyzed vegetable protein, or HVP, is produced by boiling scrap vegetables, such as soy, corn, or wheat, in hydrochloric acid and then neutralizing the solution with sodium hydroxide. The acid hydrolyzes, or breaks down, the protein in vegetables into their component amino acids.
Hydromagnesite Hydromagnesite is a hydrated magnesium carbonate mineral which generally occurs associated with the weathering products of magnesium containing minerals such as serpentine or brucite. It also sometimes appears in caves, deposited from water that has seeped through magnesium rich rocks.
Hydromechanics Hydromechanics (Gr. ubpops avuca) is the science of the mechanics of water and fluids in general, including hydrostatics or the mathematical theory of fluids in equilibrium, and hydromechanics, the theory of fluids in motion.
Hydrometallurgy Hydrometallurgy is the field of extractive metallurgy involving the use of aqueous chemistry for the recovery of metals from ores, concentrates, and recycled or residual materials. Hydrometallurgy is typically divided into three general areas:
Hydrometeorological Prediction Center The Hydrometeorological Prediction Center (HPC) is one of nine Service Centers under the umbrella of the National Centers for Environmental Prediction (NCEP), operating under the aegis of the National Weather Service, which in turn is part of the National Oceanic and Atmospheric Administration (NOAA) of the U.S.
Hydrometer [hydrometer is an instrument used for determining the specific gravity] of [[liquids. It is usually made of glass and consists of a cylindrical stem and a bulb weighted with mercury or shot to make it float upright.
Hydromylidae The small pelagic snails of the family Hydromylidae (Pruvot-Fol, 1942) lack a shell (except in their early embryonic stage).They are carnivores, equipped with swimming parapoda (fleshy, winglike outgrowths), strong jaws and grasping tentacles, often with suckers resembling those of cephalopods.
Hydronym A hydronym (from Greek hudor, "water" and onuma, "name") is a proper name of a body of water. Hydronymy is the study of hydronyms and of how bodies of water receive their names and how they are transmitted through history.
Hydropedology Hydropedology is an emerging field formed from the intertwining branches of soil science and hydrology. Similar to hydrogeology, hydroclimatology, and ecohydrology, the emphasis is connections between hydrology and other of the earth's spheres.
Hydrophile Hydrophile, from the Greek (hydros) "water" and φιλια (philia) "friendship," refers to a physical property of a molecule that can transiently bond with water (H2O) through hydrogen bonding. This is thermodynamically favorable, and makes these molecules soluble not only in water, but also in other polar solvents.
Hydrophilic-lipophilic balance The Hydrophilic-lipophilic balance of a surfactant is a measure of the degree to which it is hydrophilic or lipophilic, determined by calculating values for the different regions of the molecule, as described by Griffin in 1949Griffin WC: "Classification of Surface-Active Agents by 'HLB,'" Journal of the Society of Cosmetic Chemists 1 (1949): 311. and 1954.
Hydrophilicity plot A hydrophilicity plot is a quantitative analysis of the degree of hydrophobicity or hydrophilicity of amino acids of a protein. It is used to characterize or identify possible structure or domains of a protein.
Hydrophis semperi Hydrophis semperi is a rare sea snake found only in a single lake on the island of Luzon in the Philippines. It is noted for being one of two known species of sea snake (and the only one in its family) that is known to be found almost-exclusively in freshwater.
Hydrophobic collapse Hydrophobic collapse is a hypothesized event that occurs during the folding process of globular proteins, suggested on the basis of the observation that proteins' native states often contain a hydrophobic core of nonpolar amino acid side chains (interspersed with charged side chains that are neutralized by salt bridges) in the protein's interior, leaving most of the polar or charged residues on the solvent-exposed protein surface. The energetic stabilization conferred on the protein by the sequestration of the hydrophobic side chains from the surrounding water is thought to stabilize folding intermediates.
Hydrophobic effect The hydrophobic effect is the property that nonpolar molecules like to self-associate in the presence of aqueous solution. In the most extreme case, oils will pool together and fail to be miscible with water; detergents forming micelles and bilayers (as in soap bubbles) are another dramatic consequence of the hydrophobic effect.
Hydrophobic soil Hydrophobic soil - soil that is hydrophobic - causes water to collect on the soil surface rather than infiltrate into the ground. Wild fires generally cause soils to be hydrophobic temporarily, which increases surface runoff and erosion in post-burn sites.
Hydrophone A hydrophone is a sound-to-electricity transducer for use in water or other liquids, analogous to a microphone for air. Such a transducer can sometimes also serve as a projector (emitter), but not all have this capability, and may be destroyed if used in such a manner.
Hydroplaning (road vehicle) Hydroplaning (aquaplaning) in a road vehicle occurs when a layer of water builds between the rubber tires of the vehicle and the road surface, preventing the vehicle from responding to control inputs. It becomes, in effect, an unpowered and unsteered sled.
Hydroplates Hydroplates are a concept proposed by retired USAF colonel and mechanical engineer Walt Brown of superfast continental drift in his book titled, In the Beginning: Compelling Evidence for Creation and the Flood. Many creationists organizations such as Answers in Genesis and the Institute for Creation Research consider the hydroplate notion to be unworkable.
Hydropneumatic device North American, European, and other languages refer to hydropneumatic devices such as a hydropneumatic accumulator or pulsation dampener using very different words. In many cases this can cause a great deal of word usage confusion.
Hydropneumatic suspension Hydropneumatic is a type of automotive suspension system invented by Citroën and fitted to Citroën cars, as well as being adapted by other car manufacturers, notably Rolls-Royce, Mercedes-Benz and Peugeot. It was also used on Berliet trucks.
Hydropolis Scheduled to open in 2009, the Hydropolis in Qingdao, China, will be anchored in the Yellow Sea in water that is 16 to 20 meters deep at low tide. Guests will arrive at the hotel by yacht, which will also go to a planned land-based hydrotower, scheduled to open for the 2008 Olympic Games in Beijing.
Hydroponics Hydroponics is crop production with mineral nutrient solutions instead of soil containing silt and clay. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel or rockwool.
Hydroquinone Hydroquinone, also benzene-1,4-diol, is an aromatic organic compound which is a type of phenol, having the chemical formula C6H4(OH)2. Its chemical structure, shown in the table at right, has two hydroxyl groups bonded to a benzene ring in a para position.
Hydros Hydros was to provide the first global view of the Earth's changing soil moisture and surface freeze/thaw conditions, enabling new scientific studies of global change and atmospheric predictability, and making new hydrologic applications possible.of 16 December 2005, NASA stated it would not fund this project to completion.
Hydroscope A hydroscope is a device (camera) which is designed to see (usually far) underwater. One common use is for is for inspecting pipelines There have been various forms of it including a recent invention, the dynamic hydroscope.
Hydroseeding Hydroseeding (or hydromulching, hydraulic mulch seeding, hydraseeding) is a planting process which utilizes a slurry of seed and mulch. The slurry is transported in a tank, either truck or trailer mounted, and sprayed over prepared ground in a uniform layer; helicopters may be used in cases where larger areas must be covered.
Hydrostatic equilibrium Hydrostatic equilibrium occurs when compression due to gravity is balanced by a pressure gradient which creates a pressure gradient force in the opposite direction. The balance of these two forces is known as the hydrostatic balance.
Hydrostatic fluid In atmospheric dynamics and fluid dynamics, a hydrostatic fluid is a fluid in which fluid stresses act isotropically and fluid elements are in local equilibrium with one another. Thus, all directional fluid stresses, normally represented as vectors, can be summarized by a scalar quantity called the hydrostatic pressure, which can still depend on position.
Hydrostatic head When generating hydropower, the head is a general term used to describe the distance that a given water source has to fall before the point where power is generated. Ultimately the force responsible for hydropower is gravity, so a hydroelectricity plant with a tall/high head can produce more energy than a similar plant with a short/low head.
Hydrostatic loop A hydrostatic loop, though not often used in plumbing practice, is an arrangement of pipes formed into a vertical loop to prevent backflow of water within the plumbing potable water system. Since a siphon has a maximum height that it can work (about 33 feet), a hydrostatic loop is built higher than 33 feet.
Hydrostatic shock Hydrostatic shock is a theory of terminal ballistics that wounding effects are created by a shock wave in the tissues of the target. The term is meant to be a combination of hydrostatics with the (misnomer) effect of hydrodynamic shock.
Hydrostatic skeleton A hydrostatic skeleton or hydroskeleton is a structure found in many soft-bodied invertebrates consisting of a fluid-filled cavity, the coelom, surrounded by muscles. The pressure of the fluid and action of the surrounding muscles are used to change an organism's shape and produce movement, such as burrowing or swimming.
Hydrostatic test A hydrostatic test is the normal way in which a gas pressure vessel such as a gas cylinder or a boiler is checked for leaks or flaws. Testing is very important because such containers can explode if they fail when containing compressed gas.
Hydrothermal circulation Hydrothermal circulation in its most general sense is the circulation of hot water; 'hydros' in the Greek meaning water and 'thermos' meaning heat. Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust.
Hydrothermal synthesis Hydrothermal synthesis includes the various techniques of crystallizing substances from high-temperature aqueous solutions at high vapor pressures; also termed "hydrothermal method". The term "hydrothermal" is of geologic origin.
Hydrothermal vent A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found in places that are also volcanically active, where hot magma is relatively near the planet's surface.
Hydrothorax A hydrothorax is a condition that results from fluid accumulating in the pleural cavity. In hemothorax this fluid is blood (as in major chest injuries), in pyothorax the fluid is pus (resulting from chest infections), in chylothorax it is chylus (resulting from rupture of the thoracic duct).
Hydrotrope A hydrotrope is a compound that solubilises hydrophobic compounds in aqueous solutions. Typically, hydrotropes consist of a hydrophilic part and a hydrophobic part (like surfactants) but the hydrophobic part is generally too small to cause spontaneous self-aggregation.
Hydrotropism Hydrotropism is a directional growth response in which the direction is determined by a gradient in water concentration. The most common example is that of plant roots growing in humid air bending toward a higher relative humidity level.
HydroTexaco HydroTexaco is a Norwegian and Danish gas station chain formed after the merge of the Hydro and Texaco gas station chaines merged in 1995. In 2006 the company was bought by Reitangruppen and in the course of 2006 will be incorporated into their chain including the use of 7-Eleven brand on the service stations.
Hydrous band Hydrous is a grunge/rock band created in september 2001 by singer/songwriter/guitarist Anthony Timson,with producers Stefan Lee and Suli Hirani.The line-up was completed in march 2004 by frontman Anthony Timson with bassist Vincenz Benjamin,and drummer Gideon Letch.
Hydrous iron oxides Hydrous iron oxides, also called hydrous ferric oxides, are a class of minerals that form from the weathering of minerals that contain iron (Fe) and hydroxides (OH-), but not water. They are poorly crystalline, highly porous and have large surface areas.
Hydroxamic acid A hydroxamic acid is a class of chemical compounds sharing the same functional group in which an amine is inserted into an carboxylic acid. Its general structure is R-CO-NH-OH, with in R as an organic residue, a CO as a carbonyl group, and a hydroxylamine as NH-OH.
Hydroxycitric acid Hydroxycitric acid (HCA) is a derivative of citric acid that is extracted from the rind of the fruit of garcinia cambogia. It has shown promise as a weight-loss supplement in animal trials, but human trials have so far been disappointing.
Hydroxylapatite Hydroxylapatite, also frequently called hydroxyapatite, is a mineral. It is a naturally occurring form of calcium apatite with the formula Ca5(PO4)3(OH), but is usually written Ca10(PO4)6(OH)2 to denote that the crystal unit cell comprises two molecules.
Hydroxylation Hydroxylation is any chemical process that introduces one or more hydroxyl groups (-OH) into a compound (or radical) thereby oxidising it. In biochemistry, hydroxylation reactions are often facilitated by enzymes called hydroxylases.
Hydroxymethylbilane Hydroxymethylbilane is a molecule involved in the metabolism of porphyrin. In the third step, it is generated by the enzyme porphobilinogen deaminase , and in the next step the enzyme uroporphyrinogen III synthase converts it into uroporphyrinogen III.
Hydroxymethylfurfural Hydroxymethylfurfural, HMF or 5-(Hydroxymethyl)furfural is an aldehyde and a furan compound formed during the thermal decomposition of sugars and carbohydrates . HMF has been identified in a wide variety of heat processed foods including milk, fruit juices, spirits, honey, etc.
Hydroxystilbamidine Hydroxystilbamadine (FluoroGold®) is a fluorescent dye that emits different frequencies of light when bound to DNA and RNA. It is used as a retrograde tracer for outlining neurons, and as a histochemical stain.
Hydroxysultaine Hydroxysultaines find their main use in high-foaming shampoos, bath products and shower gels especially in conjunction with ether sulfates and alkyl sulfates. They are also used in industrial applications where high, stable foam is required.
Hydroxyurea Hydroxyurea or hydroxycarbamide (the latter being the recommended International Non-Proprietary Name), (brand names include Hydrea®) is an antineoplastic drug used in hematological malignancies. It is also used as an antiretroviral agent (e.
Hydrozoning Hydrozoning is a landscape practice that groups plants with similar water requirements together in an effort to conserve water. For example, drought tolerant plants such as sages or cactus would not be planted in a bluegrass lawn, but would be separated, since bluegrass has a higher water requirement.
Hydrus Hydrus (IPA: , , also referred to as "male Hydra" or "little Hydra") is a minor southern constellation. The constellation was one of twelve constellations created by Pieter Dirkszoon Keyser and Frederick de Houtman between 1595 and 1597, and it first appeared in Johann Bayer's Uranometria of 1603.
Hye Rim Park Hye Rim Park is a Korean-American supermodel currently signed with Trump Model Management (New York), Take 2 Models (London), Why Not Models (Milan) and CITY Models (Paris). Hye made her runway debut during the Fall/Winter 2005 season.
Hyemoschus aquaticus The water chevrotain (Hyemoschus aquaticus), also known as the fanged deer, is a small ruminant found in tropical Africa. It is the largest of the four species of chevrotains, evolutionarily primitive even-toed ungulates which are similar to deer but are barely larger than small dogs.
Hyena (comics) Hyena is the name of at least two villains in DC Comics, one male and one female, primarily, the foes of Firestorm. Both were were-hyenas who had problems with authority and resented Firestorm for interfering in their vendettas.
Hyena butter Hyena butter is a secretion from the anal gland of hyenas used to mark territory and to identify individuals by odor. The gooey substance is spread onto objects within the territory of the hyena by rubbing their posterior against the object they mark.
Hyeomillyu Hyeomillyu (Hangul: 혐일류; Hanja: 嫌日流) or The Hate Japan Wave is Korean cartoonist Yang Byeong-seol's (양병설) response to the book Manga Kenkanryu (The Hating Korea Wave). Yang's book, however, has been greatly criticized by many fellow Korean readers and media outlets for not being sufficient answer to Kenkanryu, as many readers felt it lacks any proof or logical arguments.
Hyeonjeong non Hyeonjeong non (English: Exposition of the Correct) was an essay written at the beginning of the Joseon period, defending Buddhism against the attacks of a rising antagonistic Neo-Confucian movement. It was written in a single fascicle, by the Korean Buddhist monk Gihwa (1376-1433).
Hyeonjong of Joseon King Hyeonjong of Joseon (1641-1674) was the 18th monarch of the Korean Joseon Dynasty, reigning from 1659 to 1674. His reign was mostly marked by heavy conflict among nation's political factions on various issues, especially on funeral issue.
Hyfish Hyfish is a model hydrogen powered aeroplane developed by Koni Schafroth. The model has successfully passed test flights under battery power and Smartfish is going forward with development to a 2-man aircraftHyfish Fuel Cell Treehugger News.
Hyflex Hyflex (Hypersonic Flight Experiment) was a NASDA reentry demonstrator prototype which was launched in 1996 on the only flight of the J-I launcher. It was a successor of OREX and was a precursor for the Japanese space Shuttle Hope.
Hyflux Hyflux Limited began in 1989 as Hydrochem (S) Private Limited, a trading company selling water treatment systems in Singapore, Malaysia and Indonesia and later, China. It is perhaps best known for being largely responsible for the technology behind Singapore's water recycling plants, whose output has been named "NEWater".
Hyfrydol Hyfrydol is a Welsh hymn tune which appears in a number of Christian hymnals in various arrangements. Originally composed by Rowland Prichard in 1844, and was originally published in the composer's handbook to the Lutheran Hymnal Cyfaill y Cantorion ("The Singer's Friend"), the best-known arrangement is probably that by Ralph Vaughan Williams originally for his revision of the English Hymnal; Vaughan Williams also composed some variations on this theme.
Hygiea family The Hygiea family of asteroids is a grouping of dark, carbonaceous C-type and B-type asteroids in outer main belt, the largest member of which is 10 Hygiea. About 1% of all known main belt asteroids belong to this family.
Hygieia In Greek mythology, Hygieia (Roman equivalent: Salus) was a daughter of Asclepius. She was the goddess of health, cleanliness and sanitation (and later: the moon), and played an important part in her father's cult (see also: asklepieion).
Hygiene hypothesis In medicine, the hygiene hypothesis states that a lack of early childhood exposure to infectious agents increases susceptibility to allergic diseases Strachan DP. Family size, infection and atopy: the first decade of the "hygiene hypothesis".
Hygienic Productions Hygienic Productions was a film production company based out of Wilmington, Ohio. Formed by exploitation film producer Kroger Babb, the company was in charge of promotion and production for a number of Babb's films, including the infamous Mom and Dad.
Hyginus (crater) Hyginus is a small lunar caldera located at the east end of the Sinus Medii. The crater rim is split by a long, linear rille that branches to the northwest and to the east-southeast for a total length of 220 kilometers.
Hygrocybe conica Hygrocybe conica, commonly known as the witch's hat, conical wax cap or conical slimy cap, is a colourful member of the genus Hygrocybe (the waxcaps), found across northern Europe and North America. Originally described as Hygrophorus conicus, it may actually be a complex of closely related and similar species.
Hygrocybe psittacina Hygrocybe psittacina, commonly known as the Parrot Toadstool or Parrot Waxcap, is a colourful member of the genus Hygrocybe, the waxcaps, found across Northern Europe. Originally described as Hygrophorus psittacinus, there have been at least two subspecies described, H.
Hygrocybe punicea Hygrocybe punicea, sometimes called Crimson- or Scarlet Waxy Cap, is a colourful member of the genus Hygrocybe, the waxcaps, found across Northern Europe. Originally described as Hygrophorus puniceus, it is the largest member of the genus.
Hygrometer Hygrometers are instruments used for measuring humidity. A simple form of a hygrometer is specifically known as a "psychrometer" and consists of two thermometers, one of which includes a dry bulb and the other of which includes a bulb that is kept wet to measure wet-bulb temperature.
Hygrophanous The adjective hygrophanous refers to the color change of mushroom tissue (especially the pileus surface) as it loses or absorbs water, which causes the pileipellis to become more transparent when wet and opaque when dry.
Hygrophoraceae The family Hygrophoraceae, also known as waxy caps or waxcaps, is a taxon of white-spored agarics. Among them are some of the most brightly coloured fungi encountered, often in grasslands across the northern hemisphere.
Hygrophoropsidaceae Hygrophoropsidaceae is a family of mushrooms that are gilled in appearance but lie with in the Boletales. Its genera include Austropaxillus, Tapinella and Hygrophoropsis, with the best known members being the False Chantarelle (Hygrophoropsis aurantiaca) and the tree-growing Tapinella panuoides, formerly of the genus Paxillus.
Hygrophoropsis aurantiaca Hygrophoropsis aurantiaca, commonly known as the False Chanterelle, is an orange funnel-shaped mushroom which has been confused at times with the true chanterelles, however recent work shows its affinity lies with the Boletes in the order Boletales.
Hygrophorus Hygrophorus is the type genus for the Hygrophoraceae. Members of this genus are distinguished from other members of this family by the dull coloration (tending towards whites, beiges, and dull oranges or yellows) of their fruiting bodies and microscopically by their divergent lamellar trama.
Hygroton Hygroton - trademark of Novartis Pharmaceuticals for Chlorthalidone, an antihypertensive diuretic based on Thiazide. Other drugs in this category include: Bendroflumethiazide, Chlorothiazide, Hydrochlorothiazide, Hydroflumethiazide, Methyclothiazide, Metolazone, Polythiazide, Quinethazone, and Trichlormethiazide.
Hykko Hykko is an old term, not frequently seen in present day English, but is a racial slur, inferring the inferiority of the Finnish Race The term originated during the 2nd world war period, where Fins were looked down on by the general populace after their brave victory over Germany. Germans would refer to them as Hykkon, or as a "Hykko" which was intended to produce a negative reaction.
Hyksos The Hyksos (Egyptian heqa khasewet, "foreign rulers"; Greek ) were an ethnically mixed group of Southwest Asiatic and local Semitic people (the Habiru) who invaded the eastern Nile Delta, initiating the Second Intermediate Period of ancient Egypt. They rose to power in the 17th century BC, and ruled Lower and Middle Egypt for over 100 years, forming the Fifteenth and possibly the vassal Sixteenth Dynasties of Egypt, (c.
Hyla arenicolor The Canyon Tree Frog or Arizona Tree Frog (Hyla arenicolor) is a species of tree frog native to the rocky plateau areas of southern United States, primarily in the states of New Mexico and Arizona, but it also ranges to neighboring states of Utah, Texas and Colorado, as well as into northern Mexico in the states of Michoacán, México, Guerrero, and Oaxaca.

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