Hydroxide, hī-droks′īd, n. a metallic or basic radical combined with one or more hydroxyl groups.—n. Hydrox′yl, a compound radical not yet isolated, but found in many chemical compounds.
Hydrozoa, hī-dro-zō′a, n.pl. (sing. Hydrozō′on) one of the main divisions of the sub-kingdom Cœlenterata, the other two being Ctenophora and Anthozoa or Actinozoa; they are chiefly marine organisms, soft and gelatinous, free or fixed, existing everywhere, endlessly varied in form and complexity of structure, including such great groups as hydroids, acalephs, medusans, jelly-fish, sea-blubbers, &c.—adjs. Hydrozō′an, Hydrozō′ic. [Gr. hydōr, water, zōon, an animal.]
Hydruret. Same as Hydrid.
Hyena, hī-ē′na, Hyen, hī′en, n. (Shak.) a hyæna.
Hyetal, hī′e-tal, adj. rainy.—n. Hy′etograph, a chart showing the average rainfall of the earth or any of its divisions.—adjs. Hyetograph′ic, -al.—ns. Hyetog′raphy; Hyetol′ogy; Hyetom′eter; Hyetomet′rograph. [Gr. hyetos, rain.]
Hygeian, hī-jē′an, adj. relating to health and its preservation.—ns. Hygeia (hī-jē′a), goddess of health, daughter of Æsculapius; Hy′giēne, Hygien′ics, Hy′gienism, the science which treats of the preservation of health.—adj. Hygien′ic.—adv. Hygien′ically.—n. Hy′gienist, one skilled in hygiene; Hygiol′ogy, art of the preservation of health. [Gr. hygieia—hygiēs, healthy.]
Hygrodeik, hī′gro-dīk, n. a form of hygrometer in which the atmospheric humidity is indicated by an index controlled by the heights of a wet-bulb and a dry-bulb thermometer, supported on each side of a frame on which is described a scale. [Gr. hygros, wet, deik-nynai, to show.]
Hygrometer, hī-grom′et-ėr, n. an instrument for measuring the moisture in the atmosphere, or its relative humidity.—n. Hygrom′etry, the art of measuring the moisture in the atmosphere, and of bodies generally.—adjs. Hygromet′ric, -al. [Gr. hygros, wet, metron, a measure.]
Hygroscope, hī′gro-skōp, n. an instrument for indicating the humidity of the atmosphere.—adjs. Hygroscop′ic, -al.—ns. Hygroscopic′ity; Hygrostat′ics, the art of measuring degrees of moisture. [Gr. hygros, wet, skopein, to view.]
Hyksos, hik′sos, n. the shepherd kings, apparently a Tartar race who overthrew the reigning dynasty of Lower Egypt about 2000 B.C., and reigned until overturned by the Egyptian rulers of Upper Egypt about 1700 B.C.