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[byoo-til, byoot-l] /ˈbyu tɪl, ˈbyut l/
adjective, Chemistry.
containing a butyl group.
Origin of butyl
First recorded in 1865-70; but(yric) + -yl


[byoo-til, byoot-l] /ˈbyu tɪl, ˈbyut l/
a brand of synthetic rubber prepared by polymerization of butylene containing little butadiene, particularly useful for inner tubes of automobile tires because of its leakproof qualities. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for butyl
Historical Examples
  • The stuff smelled like a mixture of spirits of ammonia and butyl mercaptan, but it did the job.

    The Highest Treason Randall Garrett
  • There are also higher alcohols, that is, those having more complex chemical formulas, such as butyl alcohol.

    Encyclopedia of Diet Eugene Christian
  • "And butyl mercaptan; I'm quite aware of that," said the Doctor quickly, to continue the tradition of omniscience.

    Skippy Bedelle Owen Johnson
  • It has the characteristic odour of the flowers, and consists of a mixture of butyl and amyl angelates and valerates.

British Dictionary definitions for butyl


/ˈbjuːˌtaɪl; -tɪl/
(modifier) of, consisting of, or containing any of four isomeric forms of the group C4H9–: butyl rubber
Word Origin
C19: from but(yric acid) + -yl
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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Word Origin and History for butyl

hydrocarbon radical, 1868, from butyric acid, a product of fermentation found in rancid butter, from Latin butyrum "butter" (see butter (n.)).

Online Etymology Dictionary, © 2010 Douglas Harper
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butyl in Medicine

butyl bu·tyl (byōōt'l)
A hydrocarbon radical, C4H9.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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butyl in Science
The radical C4H9, derived from butane.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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