\Naph"thol\, n. [Naphthalene + -ol.] (Chem.)
Any one of a series of hydroxyl derivatives of naphthalene,
analogous to phenol. In general they are crystalline
substances with a phenol (carbolic) odor.
{Naphthol blue}, {Naphthol orange}, {Naphthol yellow}
   (Chem.), brilliant dyestuffs produced from certain complex
   nitrogenous derivatives of naphthol or naphthoquinone.