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phenylalanine

[fen-l-al-uh-neen, -nin, feen-]
noun Biochemistry.
  1. a crystalline, water-soluble, essential amino acid, C6H5CH2CH(NH2)COOH, necessary to the nutrition of humans and most animals, obtained chiefly from egg white or skim milk. Abbreviation: Phe; Symbol: F

Origin of phenylalanine

First recorded in 1880–85; phenyl + alanine
Also called phen·yl·a·mi·no·pro·pi·on·ic ac·id [fen-l-uh-mee-noh-proh-pee-on-ik, -am-uh-noh-, feen-, fen-l-uh-mee-noh-, -am-uh-noh-, feen-] /ˈfɛn l əˈmi noʊ proʊ piˈɒn ɪk, -ˈæm ə noʊ-, ˈfin-, ˌfɛn l əˌmi noʊ-, -ˌæm ə noʊ-, ˌfin-/.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for phenylalanine

phenylalanine

noun
  1. an aromatic essential amino acid; a component of 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
phenylalanine in Medicine

phenylalanine

[fĕn′əl-ăl′ə-nēn′, fē′nəl-]
n.
  1. An essential amino acid that occurs as a constituent of many proteins and is normally converted to tyrosine in the body.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
phenylalanine in Science

phenylalanine

[fĕn′əl-ăl′ə-nēn′]
  1. An essential amino acid. Chemical formula: C9H11NO2. See more at amino acid.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.