(Science: chemistry) Pertaining to, or containing, gallium.
Origin: From gallium.
Pertaining to, or derived from, galls, nutgalls, and the like.
(Science: chemistry) gallic acid, 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, 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 colour with iron salts, forming tannate and gallate of iron, which are the essential ingredients of common black ink.