HYDRINA
Hy*dri"na, n. pl. Etym: [NL. See Hydra.] (Zoöl.)

Defn: The group of hydroids to which the fresh-water hydras belong.

HYDRIODATE
Hy*dri"o*date, n. Etym: [Cf. F. hydriodate.] (Zoöl.)

Defn: Same as Hydriodide.

HYDRIODIC
Hy`dri*od"ic, a. Etym: [Hydr- + iodic: cf. F. hydriodique.] (Chem.)

Defn: Pertaining to, or derived from, hydrogen and iodine; — said of an acid produced by the combination of these elements. Hydriodic acid (Chem.), a pungent, colorless gas, HI, usually prepared as a solution in water. It is strong reducing agent. Called also hydrogen iodine.

HYDRIODIDE
Hy*dri"o*dide, n. (Chem.)

Defn: A compound of hydriodic acid with a base; — distinguished from an iodide, in which only the iodine combines with the base.

HYDRO-; HYDR-
Hy"dro-, Hy"dr-.

1. A combining form from Gr. Hydra).