Online Etymology Dictionary

hydrofoil (n.): 1959, "boat that travels through water on wings," short for hydrofoil boat, originally the name of the "wings" themselves (1920); formed in English from hydro- + foil (n.).
hydrogen (n.): 1791, from French hydrogène, coined 1787 by G. de Morveau, Lavoisier, Berthollet, and Fourcroy from Greek hydr-, stem of hydros "water" (see water (n.1)) + French -gène "producing" (see -gen). So called because it forms water when exposed to oxygen. Nativized in Russian as vodorod; in German, it is wasserstoff, "water-stuff." An earlier name for it in English was Cavendish's inflammable air (1767). Hydrogen bomb first recorded 1947; shortened form H-bomb is from 1950.
hydrogenate (v.): 1809, from hydrogen + -ate (2). Related: Hydrogenated; hydrogenation.
hydrography (n.): 1550s, from hydro- + -graphy. Related: Hydrographic
hydrology (n.): 1762, from hydro- + -logy. Related: Hydrologist; hydrological (1660s).
hydrolysis (n.): "chemical decomposition by water," 1880, formed in English from hydro- + Greek lysis "a loosening, a dissolution," from lyein "to loosen, dissolve" (see lose).
hydrometer (n.): 1670s, from hydro- + meter (n.3).
hydrophobia (n.): late 14c., idroforbia, a symptom of rabies in man (sometimes used for the disease itself), from Late Latin hydrophobia (Celsius, 50 C.E.), from Greek hydrophobos "dreading water," from hydr-, stem of hydros "water" (see water (n.1)) + phobos "dread, fear" (see phobia). So called because human sufferers show aversion to water and have difficulty swallowing it.
hydrophobic (adj.): 1807, from hydrophobia + -ic.
hydroplane (n.): "motorboat that glides on the surface of water," 1895, coined by U.S. engineer Harvey D. Williams ["Sibley Journal of Engineering," Cornell University, vol. X, p.81]; from hydro- + plane (from airplane).
hydroplane (v.): by 1908, "to skim the surface of water by use of hydroplanes," from hydroplane (n.). Meaning "skid on a thin layer of water" (especially of automobile tires) first recorded 1962, properly aquaplane (itself from 1961 in this sense). Related: Hydroplaned; hydroplaning.
hydroponics (n.): 1937, formed in English from hydro- + -ponics, from Greek ponein "to labor, toil," from ponos "labor" (see span (v.)). Related: Hydroponic (adj.).
hydropower (n.): 1933, from hydro- + power (n.).
hydrosphere (n.): 1887, from hydro- + sphere.
hydrostatic (adj.): 1670s, from Greek hydro- "water" (see water (n.1)) + statikos "making to stand" (see static).
hydrotherapy (n.): 1876, from hydro- "water" + therapy.
hydrothermal (adj.): 1849, from hydro- + thermal.
hydroxide (n.): 1851, from hydro- + oxide.
hyena (n.): mid-14c., from Old French hiene, from Latin hyaena, from Greek hyaina "swine" (fem.), from hys "pig" + fem. suffix -aina. So called for its bristles. Applied to cruel, treacherous, and greedy persons since at least 1670s. Adjectival forms that have been attempted in English include hyenaish, hyenaesque, hyenic, hyenine.
hygiene (n.): 1670s, from French hygiène, ultimately from Greek hygieine techne "the healthful art," from hygies "healthy," literally "living well" (personified as the goddess Hygieia), from PIE *eyu-gwie-es- "having a vigorous life." The Greek adjective was used by Aristotle as a noun meaning "health."
hygienic (adj.): 1833, from French hygiénique, from hygiène; see hygiene. The earlier adjective was hygienal (1660s).
hygienist (n.): 1844, "an expert on cleanliness," from hygiene + -ist. Earlier was hygeist (1716). Dental sense is recorded by 1913.
hygro-: word-forming element meaning "wet, moist, moisture," from Greek hygro-, comb. form of hygros "wet, moist, fluid," from PIE root *wegw- "wet."
hygrology (n.): 1790; see hygro- + -ology.
hygrometer (n.): 1660s, from French hygromètre, from Greek hygro- (see hygro-) + -meter. Related: Hygrometry; hygrometric.
hygroscopic (adj.): 1775, from hygroscope (1660s), from hygro- + -scope.
Hyksos: c.1600, 15th dynasty of Egyptian kings (1650-1558 B.C.E.), called "Shepherd Kings," from Greek Hyksos, from Egyptian, either hiq shasu "ruler of nomads," or heqa khoswe "chief of foreign lands."
hylo-: word-forming element meaning "wood, forest; matter," from Greek hylo-, from hylos "wood; matter," of unknown origin.
Hyman: masc. proper name; see Hymie.
hymen (n.): 1610s, from French hymen (16c.), from medical Latin, ultimately from Greek hymen "membrane (especially 'virginal membrane,' the membrane par excellence); thin skin," from PIE *syu-men-, from root *syu- "to bind, sew" (see sew). Originally any membrane; present specific meaning begins with Vesalius in the 1555 edition of De humani corporis fabrica. Apparently not directly connected to Hymen, the god of marriage, but sharing the same root and supposed to be related in folk etymology.
Hymen: 1580s, Greek god of marriage, represented as a youth carrying a torch and a veil, perhaps etymologically "the joiner," literally "the one who sews" (two together); see hymen.
hymeneal (adj.): c.1600, "of or relating to a marriage;" as a noun, "wedding hymn," from 1717; from Latin hymenaeus, from Greek hymenaios "belonging to wedlock, wedding, wedding song," from Hymen, Greek god of marriage.
Hymenoptera: order of insects that includes ants, wasps, and bees, 1773, coined in Modern Latin 1748 by Linnæus from Greek hymen (genitive hymenos) "membrane" (see hymen) + pteron "wing" (see pterodactyl). Related: Hymenopterous.
hymie (n.): "Jewish male" (derogatory), by early 1980s, apparently originally among black Americans, from common Jewish masc. proper name Hymie, a pet form of Hyman, from Hebrew, literally "life" (the masc. counterpart of Eve).
hymn (n.): c.1000, from Old French ymne and Old English ymen, both from Latin hymnus "song of praise," from Greek hymnos "song or ode in praise of gods or heroes," used in Septuagint for various Hebrew words meaning "song praising God." Possibly a variant of hymenaios "wedding song," from Hymen, Greek god of marriage (see hymen), or from a PIE root *sam- "to sing" (cf. Hittite išhamai "he sings," Sanskrit saman- "hymn, song") [Watkins]. Evidence for the silent -n- dates from at least 1530.
hymnal (n.): c.1500, imnale, himnale, from Medieval Latin hymnale, from ymnus, from Latin hymnus (see hymn). As an adjective, attested from 1640s. Hymnal measure, a quatrain, usually iambic, alternately rhymed, is so called for being the preferred verse form for English hymns (e.g. "Amazing Grace"), but it has been popular in English secular poetry as well, "though it almost always suggests the hymn, directly or ironically" [Miller Williams, "Patterns of Poetry," Baton Rouge: Louisiana State University, 1986].
hyoid (adj.): 1811, from French hyoïde (16c.), from Modern Latin hyoides, from Greek hyoeides "shaped like the letter U," from hu "letter U" (in later Greek called upsilon) + -oeides "like" (see -oid).
hype (n.): "excessive or misleading publicity or advertising," 1967, American English (the verb is attested from 1937), probably in part a back-formation of hyperbole, but also from underworld slang sense "swindle by overcharging or short-changing" (1926), a back-formation of hyper "short-change con man" (1914), from prefix hyper- meaning "over, to excess." Also possibly influenced by drug addicts' slang hype, 1913 shortening of hypodermic needle. Related: Hyped; hyping. In early 18c., hyp "morbid depression of the spirits" was colloquial for hypochondria (usually as the hyp or the hyps).
hyper (adj.): 1942 as a colloquial shortening of hyperactive.
hyper-: word-forming element meaning "over, above, beyond, exceedingly, to excess," from Greek hyper (prep. and adv.) "over, beyond, overmuch, above measure," from PIE super- "over" (see super-).
hyperactive (adj.): 1852, from hyper- + active.
hyperactivity (n.): 1852, from hyper- + activity.
hyperbaric (adj.): 1930, from hyper- + Greek barys "heavy" (see grave (adj.)).
hyperbaton (n.): 1570s, "figure of speech in which the natural order of words or phrases is inverted, especially for the sake of emphasis," from Greek hyperbaton, literally "overstepping," from hyper "over" + bainein "to step" (see come).
hyperbola (n.): 1660s, from Latinized form of Greek hyperbole "extravagance," literally "a throwing beyond" (see hyperbole). Perhaps so called because the inclination of the plane to the base of the cone exceeds that of the side of the cone.
hyperbole (n.): early 15c., from Latin hyperbole, from Greek hyperbole "exaggeration, extravagance," related to hyperballein "to throw over or beyond," from hyper- "beyond" + bole "a throwing, a casting, the stroke of a missile, bolt, beam," from bol-, nominative stem of ballein "to throw" (see ballistics). Rhetorical sense is found in Aristotle and Isocrates.
hyperbolic (adj.): 1640s (iperbolical is from early 15c.), from Greek hyperbolikos "extravagant," from hyperbole "extravagance," literally "a throwing beyond" (see hyperbole). Geometric sense is from 1670s. Related: Hyperbolically.
hyperborean (adj.): 1590s, from Late Latin hyperboreanus, from Latin hyperboreus, from Greek hyperboreos "pertaining to the regions of the far north," from hyper (see hyper-) + Boreas (see Boreal). The Hyperboreans were an imagined Arctic people believed by the ancients to be distinguished by piety and happiness. Middle English had iperborie "the far north of the Earth" (mid-15c.).
hypercritical (adj.): c.1600, from hyper- + critical.
hyperdrive (n.): by 1955, an invented word of science fiction writers to describe anything that can power a space craft faster than the speed of light. See hyper- + drive (n.).