All articles starting with H

Hex key

A hex key, also called an Allen key or Allen wrench, is an L-shaped tool that drives screws and bolts with a hexagonal recess in the head.

Hex Maniac (オカルトマニア, Occult Maniac) is a female-only Pokémon trainer class debuting in Generation III, specializing in Psychic- and Ghost-types; famous for the Lumiose City 'you're not the one' ghost encounter in X and Y.

Hexa-X-II

Hexa-X-II was the European 6G flagship research project, funded by the SNS Joint Undertaking under Horizon Europe, coordinated by Nokia and running from 2023 to 2025.

Hexabromobiphenyl

Hexabromobiphenyl is a polybrominated biphenyl in which six hydrogen atoms of biphenyl are replaced by bromine atoms; it was used as a flame retardant and is now banned internationally as a persistent organic pollutant.

Hexabromocyclododecane

Hexabromocyclododecane (HBCD, also written HBCDD) is a brominated cycloaliphatic flame retardant used mainly in polystyrene building insulation, phased out globally as persistent, bioaccumulative, and toxic.

Hexachlorobenzene

Hexachlorobenzene, also called perchlorobenzene, is a fully chlorinated aromatic hydrocarbon, C6Cl6, once widely used as a fungicide before being banned from commercial production in most countries.

Hexachlorocyclohexane

Hexachlorocyclohexane (HCH) is an organochlorine insecticide, C6H6Cl6, existing as a mixture of eight stereoisomers; the gamma isomer is known as lindane, once a leading pesticide and now largely banned for agricultural use.

Hexachloroethane

Hexachloroethane, also called perchloroethane or HCE, is a colorless crystalline solid with a camphor-like odor, isolated by Michael Faraday in 1820 and used in military HC smoke.

Hexachlorophene

Hexachlorophene, sold as Phisohex, is a chlorinated bisphenol compound that was widely used for decades as a topical antiseptic in soaps and surgical scrubs before neurotoxicity concerns led to severe restrictions on its use.

HEXACO model of personality structure

HEXACO model of personality structure: six-factor taxonomy (Honesty-Humility, Emotionality, eXtraversion, Agreeableness, Conscientiousness, Openness) from lexical studies, measured by Lee and Ashton's HEXACO-PI-R, an alternative to the Big Five.

Hexaconazole

Hexaconazole, a systemic triazole (conazole) fungicide introduced by Zeneca in 1986, inhibits 14-alpha-sterol demethylase in ergosterol synthesis; used on rice, fruit, vegetables, and wood, with enantioselective activity and toxicity.

Hexacorallia

Hexacorallia (Zoantharia) is a cnidarian subclass of Anthozoa with six-fold polyp symmetry, containing six orders: sea anemones, stony corals, black corals, tube anemones, corallimorpharians, and zoanthids.

Hexactinellid

Hexactinellid (glass sponge, class Hexactinellida): marine sponge with six-rayed siliceous spicules, syncytial tissue, no mesohyl; deep-sea, 200 to over 6,000 m; oldest sponge group.

Hexade

Hexade is a 1992 two-player abstract board game by Christian Freeling, played on the Havannah hexagonal board; players place stones and win by forming a perfect six, a line, triangle, or hexagon of six stones surviving capture, with Pente-style pair capture.

Hexadecane

Hexadecane, also called n-cetane, is a straight-chain alkane with 16 carbon atoms, C₁₆H₃₄, a colorless liquid used as the cetane number 100 reference fuel for rating diesel ignition quality.

Hexadecimal

Hexadecimal, also known as base 16 or hex, is a numeral system using sixteen digits, 0–9 and A–F, serving in computing as a compact shorthand for binary.

Hexadecyl acetate

Hexadecyl acetate (cetyl acetate, palmityl acetate, CAS 629-70-9), a saturated C18 fatty ester used as a cosmetic emollient and EU-approved low-risk insect attractant pheromone, distinct from (Z)-11-hexadecenyl acetate.

Hexadecyltrimethylammonium bromide

Hexadecyltrimethylammonium bromide, better known as cetyltrimethylammonium bromide (CTAB) or cetrimonium bromide, is a quaternary ammonium salt and cationic surfactant used as a topical antiseptic, in DNA extraction, and in nanoparticle synthesis.

Hexadehydro Diels–Alder reaction

The hexadehydro-Diels–Alder (HDDA) reaction is a thermal cycloisomerization of a 1,3-diyne with an alkyne to form a benzyne, named and developed by Thomas R. Hoye and coworkers in 2012.

Hexafluorenium

Hexafluorenium (Mylaxen), C36H42N2, a bis-quaternary fluorene nondepolarizing neuromuscular blocker and reversible non-competitive plasma cholinesterase inhibitor used to prolong succinylcholine; US NDA withdrawn 1994.

Hexafluoroacetone

Hexafluoroacetone, also known as perfluoroacetone, is the perfluorinated analog of acetone, a colorless, toxic, highly reactive gas first prepared in 1941 and used chiefly as an intermediate in polymer and monomer synthesis.

Hexafluoroethane

Hexafluoroethane, known as the refrigerant R-116, is a colorless, odorless, nonflammable perfluorocarbon gas in which all six hydrogen atoms of ethane are replaced by fluorine.

Hexafluorophosphate

Hexafluorophosphate is an octahedral anion, PF6, that coordinates weakly to cations and serves as a non-nucleophilic counterion; its lithium salt, LiPF6, dominates commercial lithium-ion battery electrolytes.

Hexafluoropropylene

Hexafluoropropylene (HFP), also called hexafluoropropene, is an odorless, colorless, noncombustible gas with the formula C₃F₆ used chiefly as a comonomer in FEP fluoropolymer production and to make hexafluoropropylene oxide.

Hexagon

A hexagon is a polygon with six straight sides and six angles, regular when all sides and angles are equal, with interior angles of 120°.

Oct 10, 2026

Hexagon (Swedish technology company)

Hexagon AB is a Swedish precision measurement and positioning technology company founded in Stockholm in 1975, grown through more than 200 acquisitions including Leica Geosystems and Intergraph.

Hexagon AB

Hexagon AB is a Swedish technology company, headquartered in Stockholm, that develops precision measurement, positioning, and autonomous solutions for manufacturing, construction, aerospace, agriculture, and mining.