[ loo-seen, -sin ]

  1. a white, crystalline, water-soluble amino acid, C6H13NO2, obtained by the decomposition of proteins and made synthetically: essential in the nutrition of humans and animals. Abbreviation: Leu; Symbol: L

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Origin of leucine

First recorded in 1820–30; leuc- + -ine1

Words Nearby leucine

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How to use leucine in a sentence

British Dictionary definitions for leucine


leucin (ˈluːsɪn)

/ (ˈluːsiːn) /

  1. an essential amino acid found in many 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

Scientific definitions for leucine


[ lōōsēn′ ]

  1. An essential amino acid. Chemical formula: C6H13NO2. See more at amino acid.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.