Chapter Hydrated to Hydroidea of H by Webster's Dictionary (1913 Edition)

Hydrocorallia
(||Hy`dro*co*ral"li*a) n. pl. [NL. See Hydra, and Coral.] (Zoöl.) A division of Hydroidea, including those genera that secrete a stony coral, as Millepora and Stylaster. Two forms of zooids in life project from small pores in the coral and resemble those of other hydroids. See Millepora.

Hydrocyanate
(Hy`dro*cy"a*nate) n. (Chem.) See Hydrocyanide.

Hydrocyanic
(Hy`dro*cy*an"ic) a. [Hydro-, 2 + anic: cf. F. hydrocyanique.] (Chem.) Pertaining to, or derived from the combination of, hydrogen and cyanogen.

Hydrocyanic acid (Chem.), a colorless, mobile, volatile liquid, HCN, having a characteristic peach- blossom odor. It is one of the most deadly poisons. It is made by the action of sulphuric acid on yellow prussiate of potassium and chemically resembles hydrochloric and hydrobromic acids. Called also prussic acid, hydrogen cyanide, etc.

Hydrocyanide
(Hy`dro*cy"a*nide) n. (Chem.) A compound of hydrocyanic acid with a base; — distinguished from a cyanide, in which only the cyanogen so combines.

Hydrodynamic
(Hy`dro*dy*nam"ic Hy`dro*dy*nam"ic*al) a. [Hydro-, 1 + dynamic, - ical: cf. F. hydrodynamique.] Pertaining to, or derived from, the dynamical action of water of a liquid; of or pertaining to water power.

Hydrodynamic friction, friction produced by the viscosity of a liquid in motion.

Hydrodynamics
(Hy`dro*dy*nam"ics) n. [Hydro- , 1 + dynamics: cf. F. hydrodynamique.] That branch of the science of mechanics which relates to fluids, or, as usually limited, which treats of the laws of motion and action of nonelastic fluids, whether as investigated mathematically, or by observation and experiment; the principles of dynamics, as applied to water and other fluids.

The word is sometimes used as a general term, including both hydrostatics and hydraulics, together with pneumatics and acoustics. See Hydraulics.

Hydrodynamometer
(Hy`dro*dy`na*mom"e*ter) n. [Hydro-, 1 + dynamometer.] An instrument to measure the velocity of a liquid current by the force of its impact.

Hydro-electric
(Hy`dro-e*lec"tric) a. [Hydro- , 1 + electric.] Pertaining to, employed in, or produced by, the evolution of electricity by means of a battery in which water or steam is used.

Hydro-electric machine (Physics), an apparatus invented by Sir William Armstrong of England for generating electricity by the escape of high-pressure steam from a series of jets connected with a strong boiler, in which the steam is produced.

Hydro-extractor
(Hy`dro-ex*tract"or) n. [Hydro- , 1 + extractor.] An apparatus for drying anything, as yarn, cloth, sugar, etc., by centrifugal force; a centrifugal.

Hydroferricyanic
(Hy`dro*fer`ri*cy*an"ic) n. [Hydro-, 2 + ferricyanic.] (Chem.) Pertaining to, or containing, or obtained from, hydrogen, ferric iron, and cyanogen; as, hydroferricyanic acid. See Ferricyanic.

Hydroferrocyanic
(Hy`dro*fer`ro*cy*an"ic) a. [Hydro-, 2 + ferrocyanic.] (Chem.) Pertaining to, or containing, or obtained from, hydrogen, ferrous iron, and cyanogen; as, hydroferrocyanic acid. See Ferrocyanic.

Hydrofluate
(Hy`dro*flu"ate) n. (Chem.) A supposed compound of hydrofluoris acid and a base; a fluoride. [Archaic]

Hydrofluoric
(Hy`dro*flu*or"ic) a. [Hydro- , 2 + fluoric.] (Chem.) Pertaining to, or containing, hydrogen and fluorine; fluohydric; as, hydrofluoric acid.