[naf-thawl, -thol, nap-]
- 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.
Origin of naphthol
Also called hydroxynaphthalene.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for naphthol
Various additions have been made from time to time to the naphthol bath.
When a good method for making the naphthol was discovered in 1869, the dye was made from this.
Both the formaldehyde and the naphthol exercise tanning actions, but the process is not used in practise.Principles and Practice of Fur Dressing and Fur Dyeing
William E. Austin
The compounds formed are brilliant orange dyes, the latter being still largely consumed as “naphthol orange.”
When this compound is combined with naphthol diazo-azo dyes are produced.
- 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
C19: from naphtha + -ol 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
(năf′thôl′, -thōl′, năp′-)
- An organic compound occurring in two isomeric forms, alpha-naphthol and beta-naphthol.naphthalenol
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
[năf′thôl′, -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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.