n. A colorless compound, HON(CH3)3CH2COOH, or, in the anhydrous form, , contained in sugar-beet juice, cotton-seeds, and other vegetable products, and in urine. It forms large crystals which become anhydrous at 100° C. and attract moisture from the air, and is of considerable importance in plant physiology. Also called betain, hydroxyneurine, or trimethylglyein.