Webster's Revised Unabridged Dictionary (1913 + 1828)
Hy"dro*scope (?), n. [Hydro-, 1 + -scope.]
1. An instrument designed to mark the presence of water, especially in air.
2. A kind of water clock, used anciently for measuring time, the water tricking from an orifice at the end of a graduated tube.
Hy"dro*some (?), Hy`dro*so"ma (?), n. [NL. hydrosoma. See Hydra, and -some body.] (Zoöl.) All the zooids of a hydroid colony collectively, including the nutritive and reproductive zooids, and often other kinds.
Hy`dro*sor"bic (?), a. [Hydro-, 2 + sorbic.] (Chem.) Pertaining to, or designating, an acid obtained from sorbic acid when this takes up hydrogen; as, hydrosorbic acid.
Hy"dro*stat (?), n. A contrivance or apparatus to prevent the explosion of steam boilers.
Hy`dro*stat"ic (?), Hy`dro*stat"ic*al (?), a. [Hydro-, 1 + Gr. causing to stand: cf. F. hydrostatique. See Static.] Of or relating to hydrostatics; pertaining to, or in accordance with, the principles of the equilibrium of fluids.
The first discovery made in hydrostatics since the time of Archimedes is due to Stevinus.
Hydrostatic balance, a balance for weighing substances in water, for the purpose of ascertaining their specific gravities. -- Hydrostatic bed, a water bed. -- Hydrostatic bellows, an apparatus consisting of a water-tight bellowslike case with a long, upright tube, into which water may be poured to illustrate the hydrostatic paradox. -- Hydrostatic paradox, the proposition in hydrostatics that any quantity of water, however small, may be made to counterbalance any weight, however great; or the law of the equality of pressure of fluids in all directions. -- Hydrostatic press, a machine in which great force, with slow motion, is communicated to a large plunger by means of water forced into the cylinder in which it moves, by a forcing pump of small diameter, to which the power is applied, the principle involved being the same as in the hydrostatic bellows. Also called hydraulic press, and Bramah press. In the illustration, a is a pump with a small plunger b, which forces the water into the cylinder c, thus driving upward the large plunder d, which performs the reduced work, such as compressing cotton bales, etc.
Hy`dro*stat"ic*al*ly, adv. According to hydrostatics, or to hydrostatic principles.
Hy`dro*sta*ti"cian (?), n. One who is versed or skilled in hydrostatics. [R.]
Hy`dro*stat"ics (?), n. [Cf. F. hydrostatique.] (Physics) The branch of science which relates to the pressure and equilibrium of nonelastic fluids, as water, mercury, etc.; the principles of statics applied to water and other liquids.
Hy`dro*sul"phate (?), n. (Chem.) Same as Hydrosulphurent.
Hy`dro*sul"phide (?), n. (Chem.) One of a series of compounds, derived from hydrogen sulphide by the replacement of half its hydrogen by a base or basic radical; as, potassium hydrosulphide, KSH. The hydrosulphides are analogous to the hydrates and include the mercaptans.
Hy`dro*sul"phite (?), n. (Chem.) A saline compound of hydrosulphurous acid and a base. [R.]
Hy`dro*sul"phu*ret (?), n. (Chem.) A hydrosulphide. [Archaic]
Hy`dro*sul"phu*ret`ed (?), a. (Chem.) Combined with hydrogen sulphide.
Hy`dro*sul*phu"ric (?), a. [Hydro-, 2 + sulphuric.] (Chem.) Pertaining to, or derived from, hydrogen and sulphur; as, hydrosulphuricacid, a designation applied to the solution of hydrogen sulphide in water.
Hy`dro*sul"phur*ous (?), a. (Chem.) Pertaining to, or designating, an acid obtained by the reduction of sulphurous acid. See Hyposulphurous acid, under Hyposulphurous.
Hy`dro*tel"lu*rate (?), n. (Chem.) A salt formed by the union of hydrotelluric acid and the base.
Hy`dro*tel*lu"ric (?), a. [Hydro-, 2 + telluric.] (Chem.) Formed by hydrogen and tellurium; as, hydrotelluric acid, or hydrogen telluride.
Hy`dro*the"ca (?), n.; pl. L. Hydrothecæ (#), E. Hydrothecas (#). [NL., fr. E. hydra + Gr. a box.] (Zoöl.) One of the calicles which, in some Hydroidea (Thecaphora), protect the hydrants. See Illust. of Hydroidea, and Campanularian.
Hy`dro*ther"a*py (?), n. [Hydro-, 1 + therapy.] (Med.) See Hydropathy.
Hy`dro*ther"mal (?), a. [Hydro-, 1 + thermal.] Of or pertaining to hot water; -- used esp. with reference to the action of heated waters in dissolving, redepositing, and otherwise producing mineral changes within the crust of the globe.
Hy`dro*tho"rax (?), n. [Hydro-, 1 + thorax.] (Med.) An accumulation of serous fluid in the cavity of the chest.
Hy*drot"ic (?), a. [Gr. "y`dwr water: cf. Gr. moisture, F. hydrotique.] Causing a discharge of water or phlegm. -- n. (Med.) A hydrotic medicine.
Hy*drot"ic*al (?), a. Hydrotic.
Hy"dro*trope (?), n. [Hydro-, 1 + Gr. to turn, direct.] A device for raising water by the direct action of steam; a pulsometer.
Hy`dro*trop"ic (?), a. [See Hydrotrope.] (Bot.) Turning or bending towards moisture, as roots.
Hy*drot"ro*pism (?), n. (Bot.) A tendency towards moisture.
Hy"drous (?), a. [Gr. "y`dwr water.]
1. Containing water; watery.
2. (Chem.) Containing water of hydration or crystallization.
Hy`dro*xan"thane (?), n. (Chem.) A persulphocyanate. [Obs.]
Hy`dro*xan"thic (?), a. [Hydro-, 2 + xanthic.] (Chem.) Persulphocyanic.
Hy*drox"ide (?), n. [Hydro-, 2 + oxide.] (Chem.) A hydrate; a substance containing hydrogen and oxygen, made by combining water with an oxide, and yielding water by elimination. The hydroxides are regarded as compounds of hydroxyl, united usually with basic element or radical; as, calcium hydroxide ethyl hydroxide.
Hy*drox"y- (?). (Chem.) A combining form, also used adjectively, indicating hydroxyl as an ingredient.
Hydroxy acid (Chem.), an organic acid, having (besides the hydroxyl group of the carboxyl radical) an alcoholic hydroxyl group, and thus having the qualities of an alcohol in addition to its acid properties; as, lactic and tartaric acids are hydroxy acids.
Hy*drox"yl (?), n. [Hydro-, 2 + oxygen + -yl.] (Chem.) A compound radical, or unsaturated group, HO, consisting of one atom of hydrogen and one of oxygen. It is a characteristic part of the hydrates, the alcohols, the oxygen acids, etc.
Hy*drox`yl*am"ine (?), n. [Hydroxyl + amine.] (Chem.) A nitrogenous, organic base, NH2.OH, resembling ammonia, and produced by a modified reduction of nitric acid. It is usually obtained as a volatile, unstable solution in water. It acts as a strong reducing agent.
Hy`dro*zo"a (?), n. pl. [NL., fr. E. hydra + Gr. an animal.] (Zoöl.) The Acalephæ; one of the classes of cœlenterates, including the Hydroidea, Discophora, and Siphonophora.
Hy`dro*zo"al (?), a. (Zoöl.) Of or pertaining to the Hydrozoa.
Hy`dro*zo"ön (?), n.; pl. L. Hydrozoa (#), E. Hydrozoöns (#). [NL.] (Zoöl.) One of the Hydrozoa.
Hy"dru*ret (?), n. [Hydro-, 2] (Chem.) A binary compound of hydrogen; a hydride. [Obs.]
Hy"drus (?), n. [L., a water serpent; also, a certain constellation, Gr. "y`dros.] (Astron.) A constellation of the southern hemisphere, near the south pole.
Hye (?), n. & v. See Hie. [Obs.]
Hy*e"mal (?), a. [L. hyemalis, or better hiemalis, fr. hyems, hiems, winter: cf. F. hyémal.] Belonging to winter; done in winter.
Sir T. Browne.
Hy"e*mate (?), v. i. [L. hiemare, hiematum. See Hyemal.] To pass the winter. [Obs. & R.]
Hy`e*ma"tion (?), n. [L. hiematio.]
1. The passing of a winter in a particular place; a wintering.
2. The act of affording shelter in winter. [Obs.]
Hy"en (?), n. [F. hy\'8ane.] A hyena. [Obs.]
Hy*e"na (?), n.; pl. Hyenas (#). [L. hyaena, Gr. , orig., a sow, but usually, a Libyan wild beast, prob., the hyena, fr. hog: cf. F. hy\'8ane. See Sow female hog.] (Zoöl.) Any carnivorous mammal of the family Hyænidæ, of which three living species are known. They are large and strong, but cowardly. They feed chiefly on carrion, and are nocturnal in their habits. [Written also hyæna.]
&hand; The striped hyena (Hyæna striata) inhabits Southern Asia and a large part of Africa. The brown hyena (H. brunnea), and the spotted hyena (Crocuta maculata), are found in Southern Africa. The extinct cave hyena (H. spelæa) inhabited England and France.
Cave hyena. See under Cave. -- Hyena dog (Zoöl.), a South African canine animal (Lycaon venaticus), which hunts in packs, chiefly at night. It is smaller than the common wolf, with very large, erect ears, and a bushy tail. Its color is reddish or yellowish brown, blotched with black and white. Called also hunting dog.
Hy"e*tal (?), a. [Gr. rain, from to rain.] Of or pertaining to rain; descriptive of the distribution of rain, or of rainy regions.
Hy"e*to*graph (?), n. [Gr. rain + -graph.] A chart or graphic representation of the average distribution of rain over the surface of the earth.
Hy`e*to*graph"ic (?), a. Of or pertaining to to hyetography.
Hy`e*tog"ra*phy (?), n. The branch of physical science which treats of the geographical distribution of rain.
Hy*ge"ia (?), n. [L. Hygea, Hygia, fr. Gr. , , health, , Hygeia, fr. sound, healthy.] (Classic Myth.) The goddess of health, daughter of Esculapius.
Hy*ge"ian (?), a. Relating to Hygeia, the goddess of health; of or pertaining to health, or its preservation.
Hy"ge*ist (?), n. One skilled in hygiena; a hygienist.
Hy"gie*ist (?), n. A hygienist.
Hy"gi*ene (?), n. [F. hygi\'8ane. See Hygeia.] That department of sanitary science which treats of the preservation of health, esp. of households and communities; a system of principles or rules designated for the promotion of health.
Hy`gi*en"ic (?), a. [Cf. F. hygiénique.] Of or pertaining to health or hygiene; sanitary.
Hy`gi*en"ics, n. The science of health; hygiene.
Hy"gi*en*ism (?), n. Hygiene.
Hy"gi*en*ist, n. One versed in hygiene.
Hy`gi*ol"o*gy (?), n. [Gr. health + -logy.] A treatise on, or the science of, the preservation of health. [R.]
Hy"grine (?), n. [From Gr. moist.] (Chem.) An alkaloid associated with cocaine in coca leaves (Erythroxylon coca), and extracted as a thick, yellow oil, having a pungent taste and odor.
Hy"gro*deik (?), n. [Gr. wet, moist, and to show.] (Physics) A form of hygrometer having wet and dry bulb thermometers, with an adjustable index showing directly the percentage of moisture in the air, etc.
Hy"gro*graph (?), n. [Gr. wet + -graph.] (Physics) An instrument for recording automatically the variations of the humidity of the atmosphere.
Hy*grol"o*gy (?), n. [Gr. wet + -logy: cf. F. hygrologie.] (Med.) The science which treats of the fluids of the body.
Hy*grom"e*ter (?), n. [Gr. wet, moist + -meter: cf. F. hygrom\'8atre.] (Physics) An instrument for measuring the degree of moisture of the atmosphere.
Daniell's hygrometer, a form of hygrometer consisting of a bent glass tube terminating in two bulbs, the one covered with muslin, the other of black glass, and containing ether and a thermometer. Ether being poured on the muslin, the black ball, cooled by the evaporation of the ether within, is soon covered with dew; at this moment, the inclosed thermometer gives the dew-point, and this, compared with the reading of one in the air, determines the humidity.
Hy`gro*met"ric (?), Hy`gro*met"ric*al (?), a. [Cf. F. hygrométrique.]
1. Of or pertaining to hygrometry; made with, or according to, the hygrometer; as, hygrometric observations.
2. Readily absorbing and retaining moisture; as, hygrometric substances, like potash.
Hy*grom"e*try (?), n. [Cf. F. hygrométrie.] (Physics) That branch of physics which relates to the determination of the humidity of bodies, particularly of the atmosphere, with the theory and use of the instruments constructed for this purpose.
Hy*groph"a*nous (?), a. [Gr. wet + to show.] Having such a structure as to be diaphanous when moist, and opaque when dry.
Hy`groph*thal"mic (?), a. [Gr. wet + E. ophthalmic.] (Anat.) Serving to moisten the eye; -- sometimes applied to the lachrymal ducts.
Hy"gro*plasm (?), n. [Gr. wet + form, mold.] (Biol.) The fluid portion of the cell protoplasm, in opposition to stereoplasm, the solid or insoluble portion. The latter is supposed to be partly nutritive and partly composed of idioplasm.
Hy"gro*scope (?), n. [Gr. wet + -scope: cf. F. hygroscope.] (Physics) An instrument which shows whether there is more or less moisture in the atmosphere, without indicating its amount.
Hy`gro*scop"ic (?), a. [Cf. F. hygroscopique.]
1. Of or pertaining to, or indicated by, the hygroscope; not readily manifest to the senses, but capable of detection by the hygroscope; as, glass is often covered with a film of hygroscopic moisture.
2. Having the property of readily inbibing moisture from the atmosphere, or of the becoming coated with a thin film of moisture, as glass, etc.
Hy`gro*sco*pic"i*ty (?), n. (Bot.) The property possessed by vegetable tissues of absorbing or discharging moisture according to circumstances.
Hy`gro*stat"ics (?), n. [Gr. wet + . See Statics.] The science or art of comparing or measuring degrees of moisture.
Hyke (?), n. See Haik, and Huke.
Hy"læ*o*saur` (?), Hy`læ*o*sau"rus (?), n. [NL. hylaeosaurus, fr. Gr. belonging to a forest (fr. wood) + a lizard.] (Paleon.) A large Wealden dinosaur from the Tilgate Forest, England. It was about twenty feet long, protected by bony plates in the skin, and armed with spines.
Hy*lar"chi*cal (?), a. [Gr. wood, matter + : cf. F. hylarchique. See Archical.] Presiding over matter. [Obs.]
Hy"le*o*saur" (?), n. Same as Hylæosaur.
Hyl"ic (?), a. Of or pertaining to matter; material; corporeal; as, hylic influences.
Hy"li*cist (?), n. [Gr. adj., material, fr. wood, matter.] A philosopher who treats chiefly of matter; one who adopts or teaches hylism.