gal·lic acid /ˈgælɪk, ˈgɔlɪk-/
gal·lic acid /ˌgælɪk, ˌgɔlɪk-/ 名詞
Gal·lic a. Pertaining to, or derived from, galls, nutgalls, and the like.
Gallic acid Chem., an organic acid, very widely distributed in the vegetable kingdom, being found in the free state in galls, tea, etc., and produced artificially. It is a white, crystalline substance, C6H2(HO)3.CO2H, with an astringent taste, and is a strong reducing agent, as employed in photography. It is usually prepared from tannin, and both give a dark color with iron salts, forming tannate and gallate of iron, which are the essential ingredients of common black ink.
gallic acid
n : a colorless crystalline acid obtained from tannin