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alpha-naphthol

[al-fuh-naf-thawl, -thol, -nap-] /ˌæl fəˈnæf θɔl, -θɒl, -ˈnæp-/
noun, Chemistry
1.
See under naphthol.

naphthol

[naf-thawl, -thol, nap-] /ˈnæf θɔl, -θɒl, ˈnæp-/
noun, Chemistry
1.
either of two isomeric hydroxyl derivatives, C 1 0 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.
Origin
1840-1850
1840-50; naphth- + -ol1
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for alpha-naphthol

naphthol

/ˈnæfθɒl; ˈnæp-/
noun
1.
a white crystalline solid having two isomeric forms, alpha-naphthol, used in dyes, and beta-naphthol, used in dyes and as an antioxidant. Formula: C10H7OH
Word Origin
C19: from naphtha + -ol1
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
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alpha-naphthol in Medicine

naphthol naph·thol (nāf'thôl', -thōl', nāp'-) or naph·tol (-tôl, -tōl)
n.
An organic compound occurring in two isomeric forms, alpha-naphthol and beta-naphthol. Also called naphthalenol.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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alpha-naphthol in Science
naphthol
  (nāf'thôl', -thōl', nāp'-)   
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 © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for alpha-naphthol

naphthol

either of two colourless, crystalline organic compounds derived from naphthalene and belonging to the phenol family; each has the molecular formula C10H7OH. Both compounds have long been identified with the manufacture of dyes and dye intermediates; they also have important uses in other areas of the chemical industry.

Learn more about naphthol with a free trial on Britannica.com
Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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