| 1. | Also called orthoboric acid. Chemistry, Pharmacology. a white, crystalline acid, H3BO3, occurring in nature or prepared from borax: used chiefly in the manufacture of ceramics, cements, glass, and enamels, for fireproofing, and in medicine in aqueous solution as a mild antiseptic. |
| 2. | Chemistry. any of a group of acids containing boron. |

| boric acid n. A water-soluble white or colorless crystalline compound, H3BO3, used as an antiseptic and preservative and in fireproofing compounds, cosmetics, cements, and enamels. |
boric acid bo·ric acid (bôr'ĭk)
n.
A water-soluble white or colorless crystalline compound used as an antiseptic and preservative.