/naf"thawl, -thol, nap"-/ , n. Chem.
either of two isomeric hydroxyl derivatives, C 10 H 7 OH, of naphthalene (alpha-naphthol or 1-naphthol and beta-naphthol or 2-naphthol) , white or yellowish crystals, with a phenolic odor, that darken on exposure to light: used chiefly in dyes, drugs, perfumes, and insecticides. Also called hydroxynaphthalene .
[ 1840-50; NAPHTH- + -OL 1 ]