[al-kuh-ley-shuh n]
noun Chemistry.
  1. the replacement of a hydrogen atom in an organic compound by an alkyl group.
  2. the addition of a paraffin to an olefin, done in the manufacture of gasoline.

Origin of alkylation

First recorded in 1895–1900; alkyl + -ation Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for alkylation


  1. the attachment of an alkyl group to an organic compound, usually by the addition or substitution of a hydrogen atom or halide group
  2. the addition of an alkane hydrocarbon to an alkene in producing high-octane fuels
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

alkylation in Medicine


  1. A process in which one or more alkyl groups are substituted for hydrogen atoms in an organic compound.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.