alpha-naphthol

[ al-fuh-naf-thawl, -thol, -nap- ]
/ ˌæl fəˈnæf θɔl, -θɒl, -ˈnæp- /

noun Chemistry.

See under naphthol.

Definition for alpha-naphthol (2 of 2)

naphthol
[ naf-thawl, -thol, nap- ]
/ ˈnæf θɔl, -θɒl, ˈnæp- /

noun Chemistry.

either of two isomeric hydroxyl derivatives, C10H7OH, 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.

Origin of naphthol

First recorded in 1840–50; naphth- + -ol1

Example sentences from the Web for alpha-naphthol

  • Practically the only phenol that is used is the beta-naphthol; alpha-naphthol is occasionally used, but not often.

  • Alpha-naphthol for dark reds from Primuline, greys from Diamine blues, Neutral grey, etc.

British Dictionary definitions for alpha-naphthol

naphthol
/ (ˈnæfθɒl, ˈnæp-) /

noun

a white crystalline solid having two isomeric forms, alpha-naphthol, used in dyes, and beta-naphthol, used in dyes and as an antioxidant. Formula: C 10 H 7 OH

Word Origin for naphthol

C19: from naphtha + -ol 1

Medical definitions for alpha-naphthol

naphthol
[ năfthôl′, -thōl′, năp- ]

n.

An organic compound occurring in two isomeric forms, alpha-naphthol and beta-naphthol. naphthalenol

Scientific definitions for alpha-naphthol

naphthol
[ năfthôl′, -thōl′, năp- ]

A poisonous organic compound occurring in two isomeric forms. Both isomers are important in the manufacture of dyes, and also in making antiseptics, insecticides, and tanning agents. Naphthol consists of a hydroxyl group (OH) attached to naphthalene. Chemical formula: C10H8O.