Hy′dri‐od″ic (?), a. [Hydr- + iodic: cf. F. hydriodique.] (Chem.) 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 iodide.