[ ahy-suh-loo-seen, -sin ]

  1. a crystalline amino acid, C6H13O2, occurring in proteins, that is essential to the nutrition of humans and animals. Abbreviation: Ile; Symbol: I

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Origin of isoleucine

First recorded in 1900–05; iso- + leucine

Words Nearby isoleucine Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

British Dictionary definitions for isoleucine


/ (ˌaɪsəʊˈluːsiːn, -sɪn) /

  1. an essential amino acid that occurs in proteins and is formed by protein hydrolysis

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 isoleucine


[ ī′sə-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.