- a white, crystalline, water-soluble, poisonous, solid, phenolic compound, C6H3(OH)3, obtained by heating gallic acid and water: used chiefly as a developer in photography, as a mordant for wool, in dyeing, and in medicine in the treatment of certain skin conditions.
- a white lustrous crystalline soluble phenol with weakly acidic properties; 1,2,3-trihydroxybenzene: used as a photographic developer and for absorbing oxygen. Formula: C 6 H 3 (OH) 3
