What does "diet" mean?

Diet: A course of food selected with reference to a particular state of health; prescribed allowance of food; regimen prescribed. To fast like one that takes diet. Shak. Diet kitchen, a kitchen in which diet is prepared for invalids; a charitable establishment that provides proper food for the sick poor.

Additional senses

  1. 2.To cause to take food; to feed. [R.] Shak.
  2. 3.To cause to eat and drink sparingly, or by prescribed rules; to regulate medicinally the food of. She diets him with fasting every day. Spenser.
  3. 4.To eat; to take one's meals. [Obs.] Let him . . . diet in such places, where there is good company of the nation, where he traveleth. Bacon.
  4. 5.To eat according to prescribed rules; to ear sparingly; as, the doctor says he must diet.
  5. 6.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.

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