The monosodium salt of the natural amino acid L-glutamine (
C5H8NNaO4), used as a food additive to enhance flavor; abbreviated
MSG. It is usually marketed as the monhydrate (
C5H8NNaO4.H2O). It is commmonly used in Chinese-American restaurants, and has been identified as a main cause of
Chinese restaurant syndrome. [
WordNet 1.5]