phenylalanine phenylacetic • phenylamide · · · Info · Definitions · Characters · · phenylalanine · · Text Latin · · Script 13 · · Length Definitions · · · (noun) 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. · · Noun Definition 1 Characters · · a latin small letter a U+0061 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 l latin small letter l U+006C n latin small letter n U+006E p latin small letter p U+0070 y latin small letter y U+0079