Phenylalanine
WordNet
noun
(1) An essential amino acid found in proteins and needed for growth of children and for protein metabolism in children and adults; abundant in milk and eggs; it is normally converted to tyrosine in the human body
WiktionaryText
Noun
- An essential amino acid C9H11NO2 found in most animal proteins; it is essential for growth; the inability to metabolize it leads to phenylketonuria; it is a constituent of aspartame.