[lahy-seen, -sin]
noun Biochemistry.
  1. a crystalline, basic, amino acid, H2N(CH2)4CH(NH2)COOH, produced chiefly from many proteins by hydrolysis, essential in the nutrition of humans and animals. Abbreviation: Lys; Symbol: K

Origin of lysine

First recorded in 1890–95; lys- + -ine2 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for lysine

Historical Examples of lysine

British Dictionary definitions for lysine


  1. an essential amino acid that occurs in proteins
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

lysine in Medicine


[līsēn′, -sĭn]
  1. An essential amino acid derived from the hydrolysis of proteins and required by the body for optimum growth.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

lysine in Science


  1. An essential amino acid. Chemical formula: C6H14N2O2. See more at amino acid.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.