Pyr`o*gal"lol (?), n. [Pyrogallic + -ol.] Chem.
A phenol metameric with phloroglucin, obtained by the distillation of gallic acid as a poisonous white crystalline substance having acid properties, and hence called also pyrogallic acid. It is a strong reducer, and is used as a developer in photography and in the production of certain dyes.
© Webster 1913.