y, or by prescribed rules; to regulate medicinally the food of.5. (v. i.) To eat; to take one's meals.6. (v. i.) To eat according to prescribed rules; to ear sparingly; as, the doctor says he must diet.7. (n.) A legislative or administrative assembly in Germany, Poland, and some other countries of Europe; a deliberative convention; a council; as, the Diet of Worms, held in 1521.International Stand