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di·et 1 (dīĭt)
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n.
1. The usual food and drink of a person or animal.
2. A regulated selection of foods, as for medical reasons or cosmetic weight loss.
3. Something used, enjoyed, or provided regularly: subsisted on a diet of detective novels during his vacation.
adj.
1. Of or relating to a food regimen designed to promote weight loss in a person or an animal: the diet industry.
2.
a. Having fewer calories.
b. Sweetened with a noncaloric sugar substitute.
3. Designed to reduce or suppress the appetite: diet pills; diet drugs.
v. di·et·ed, di·et·ing, di·ets
v.intr.
To eat and drink according to a regulated system, especially so as to lose weight or control a medical condition.
v.tr.
To regulate or prescribe food and drink for.

[Middle English diete, from Old French, from Latin diaeta, way of living, diet, from Greek diaita, back-formation from diaitāsthai, to live one's life, middle voice of diaitān, to treat.]

diet·er n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
di·et 2 (dīĭt)
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n.
1. A national or local legislative assembly in certain countries, such as Japan.
2. A formal general assembly of the princes or estates of the Holy Roman Empire.

[Middle English diete, day's journey, day for meeting, assembly, from Medieval Latin diēta, alteration (influenced by Latin diēs, day) of Latin diaeta, daily routine; see DIET1.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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