Essential Amino Acid
Definition: essential amino acid
essential amino acid: An amino acid necessary for growth but which cannot be synthesized by monogastric animals and has to be obtained from the food supply. (NOTE: The essential amino acids are: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine, arginine, and histidine.) Understanding essential amino acids helps farmers formulate balanced diets for their livestock.