hydration (n.) Look up hydration at Dictionary.com
1854, noun of action from hydrate.
hydraulic (adj.) Look up hydraulic at Dictionary.com
c. 1600, from Greek hydraulikos organon "water organ," from hydr-, stem of hydor "water" (see water (n.1)) + aulos "musical instrument, hollow tube" (see alveolus). Extended by the Romans to other kinds of water engines.
hydraulics (n.) Look up hydraulics at Dictionary.com
1670s, from hydraulic; also see -ics.
hydric (adj.) Look up hydric at Dictionary.com
1796 as a term in chemistry, "of or containing hydrogen;" 1918 in ecology; see hydro- + -ic.
hydro Look up hydro at Dictionary.com
short for hydroelectric, from 1916.
hydro- Look up hydro- at Dictionary.com
before vowels hydr-, word-forming element meaning "water," from Greek hydro-, comb. form of hydor "water" (see water (n.1)). Also sometimes a comb. form of hydrogen.
hydrocarbon (n.) Look up hydrocarbon at Dictionary.com
"compound of hydrogen and carbon," 1826, formed in English from hydrogen + carbon.
hydrocephalus (n.) Look up hydrocephalus at Dictionary.com
1660s, medical Latin, from Greek hydro- "water" (see water (n.1)) + kephale "head" (see cephalo-). Related: Hydrocephalic; hydrocephalous.
hydrochloric (adj.) Look up hydrochloric at Dictionary.com
1817, in hydrochloric acid (proposed 1814 by Gay-Lussac); see hydro- + chloric (see chlorine).
hydrodynamic (adj.) Look up hydrodynamic at Dictionary.com
1828, from hydro- + dynamic (adj.). Related: Hydrodynamics (1779).
hydroelectric (adj.) Look up hydroelectric at Dictionary.com
1827, formed in English from hydro- + electric. Related: Hydroelectricity.
hydrofoil (n.) Look up hydrofoil at Dictionary.com
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.) Look up hydrogen at Dictionary.com
1791, from French hydrogène, coined 1787 by G. de Morveau, Lavoisier, Berthollet, and Fourcroy from Greek hydr-, stem of hydor "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.) Look up hydrogenate at Dictionary.com
1809, from hydrogen + -ate (2). Related: Hydrogenated; hydrogenation.
hydrography (n.) Look up hydrography at Dictionary.com
1550s, from hydro- + -graphy. Related: Hydrographic
hydrology (n.) Look up hydrology at Dictionary.com
1762, from hydro- + -logy. Related: Hydrologist; hydrological (1660s).
hydrolysis (n.) Look up hydrolysis at Dictionary.com
"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.) Look up hydrometer at Dictionary.com
1670s, from hydro- + meter (n.3).
hydrophobia (n.) Look up hydrophobia at Dictionary.com
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 hydor "water" (see water (n.1)) + phobos "dread, fear" (see phobia). So called because human sufferers show aversion to water and have difficulty swallowing it. In Old English as wæterfyrhtness.
hydrophobic (adj.) Look up hydrophobic at Dictionary.com
1807, from hydrophobia + -ic.
hydroplane (n.) Look up hydroplane at Dictionary.com
"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.) Look up hydroplane at Dictionary.com
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.) Look up hydroponics at Dictionary.com
1937, formed in English from hydro- + -ponics, from Greek ponein "to labor, toil," from ponos "labor" (see span (v.)). Related: Hydroponic (adj.).
hydropower (n.) Look up hydropower at Dictionary.com
1933, from hydro- + power (n.).
hydrosphere (n.) Look up hydrosphere at Dictionary.com
1887, from hydro- + sphere.
hydrostatic (adj.) Look up hydrostatic at Dictionary.com
1670s, from Greek hydro- "water" (see water (n.1)) + statikos "making to stand" (see static).
hydrotherapy (n.) Look up hydrotherapy at Dictionary.com
1876, from hydro- "water" + therapy.
hydrothermal (adj.) Look up hydrothermal at Dictionary.com
1852, from hydro- + thermal (adj.); 1855 in geology.
hydroxide (n.) Look up hydroxide at Dictionary.com
1851, from hydro- + oxide.
hyena (n.) Look up hyena at Dictionary.com
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.) Look up hygiene at Dictionary.com
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.) Look up hygienic at Dictionary.com
1833, from French hygiénique, from hygiène; see hygiene. The earlier adjective was hygienal (1660s).
hygienist (n.) Look up hygienist at Dictionary.com
1844, "an expert on cleanliness," from hygiene + -ist. Earlier was hygeist (1716). Dental sense is recorded by 1913.
hygro- Look up hygro- at Dictionary.com
word-forming element meaning "wet, moist, moisture," from Greek hygro-, comb. form of hygros "wet, moist, fluid," from PIE root *wegw- "wet."
hygrology (n.) Look up hygrology at Dictionary.com
1790; see hygro- + -ology.
hygrometer (n.) Look up hygrometer at Dictionary.com
1660s, from French hygromètre, from Greek hygro- (see hygro-) + -meter. Related: Hygrometry; hygrometric.
hygroscopic (adj.) Look up hygroscopic at Dictionary.com
1775, from hygroscope (1660s), from hygro- + -scope.
Hyksos Look up Hyksos at Dictionary.com
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- Look up hylo- at Dictionary.com
word-forming element meaning "wood, forest; matter," from Greek hylo-, from hylos "wood; matter," of unknown origin.
Hyman Look up Hyman at Dictionary.com
masc. proper name; see Hymie.
hymen (n.) Look up hymen at Dictionary.com
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 Look up Hymen at Dictionary.com
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.) Look up hymeneal at Dictionary.com
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 Look up Hymenoptera at Dictionary.com
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.) Look up hymie at Dictionary.com
"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.) Look up hymn at Dictionary.com
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" (cognates: Hittite išhamai "he sings," Sanskrit saman- "hymn, song") [Watkins]. Evidence for the silent -n- dates from at least 1530.
hymnal (n.) Look up hymnal at Dictionary.com
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 (such as "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.) Look up hyoid at Dictionary.com
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.) Look up hype at Dictionary.com
"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.) Look up hyper at Dictionary.com
1942 as a colloquial shortening of hyperactive.