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ethyl

[eth-uh l]
adjective
  1. Chemistry. containing the ethyl group, as ethyl ether, C4H10O.
noun
  1. a type of antiknock fluid, containing tetraethyl lead and other ingredients for a more even combustion.

Origin of ethyl

< German Ethyl, coined by J. von Liebig in 1834; see ether, -yl
Related formsnon·eth·yl, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for ethyl

ethyl

noun
  1. (modifier) of, consisting of, or containing the monovalent group C 2 H 5-ethyl group or radical
Derived Formsethylic (ɪˈθɪlɪk), adjective

Word Origin for ethyl

C19: from eth (er) + -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
Word Origin and History for ethyl

1838, modeled on German äthyl (Liebig), from Greek aither (see ether) + -yl. Ethyl alcohol, under other names, was widely used in medicine by 13c.

Online Etymology Dictionary, © 2010 Douglas Harper
ethyl in Medicine

ethyl

[ĕth′əl]
n.
  1. The univalent hydrocarbon radical C2H5.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
ethyl in Science

ethyl

[ĕth′əl]
  1. The radical C2H5, derived from ethane.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.