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diet

1 American  
[dahy-it] / ˈdaɪ ɪt /

noun

  1. food and drink considered in terms of its qualities, composition, and its effects on health.

    The ad shows milk and dairy as a wholesome part of our daily diet.

  2. a particular selection of food, especially as designed or prescribed to improve a person's physical condition or to prevent or treat a disease.

    A diet low in sugar is often recommended for diabetes prevention.

  3. a selection of food that emphasizes caloric restriction or otherwise limits the amount a person eats, usually intended to induce weight loss.

    No pie for me, I'm on a diet.

  4. the foods eaten, as by a particular person or group.

    The Mediterranean diet consists historically of fish, fruit, vegetables, whole grains, and nuts.

  5. food or feed habitually eaten or provided.

    The rabbits were fed a diet of carrots and lettuce.

  6. anything that is habitually provided or partaken of.

    Television has given us a steady diet of reality shows and police procedurals.


adjective

  1. suitable for consumption as part of a selection of food intended to induce weight loss.

    I usually drink diet soft drinks.

  2. formulated to be lower in calories, fat, sugar, etc. than a similar food.

    The diet version of the cookie does taste different.

verb (used without object)

  • diets,
    present (3rd person singular)
  • dieted,
    past participle,  past
  • dieting
    present participle
  1. to select or limit the food one eats to improve one's physical condition or to lose weight.

    I've dieted all month and lost only one pound.

  2. to eat or feed according to the requirements of a particular or prescribed selection of food.

verb (used with object)

  • diets,
    present (3rd person singular)
  • dieted,
    past participle,  past
  • dieting
    present participle
  1. to regulate the food of, especially in order to improve the physical condition.

    They dieted the dog to a healthy weight of 20 pounds.

  2. to feed.

diet 2 American  
[dahy-it] / ˈdaɪ ɪt /

noun

  1. the legislative body of certain countries, as Japan.

  2. the general assembly of the estates of the former Holy Roman Empire.


diet 1 British  
/ ˈdaɪət /

noun

    1. a specific allowance or selection of food, esp prescribed to control weight or in disorders in which certain foods are contraindicated

      a salt-free diet

      a 900-calorie diet

    2. ( as modifier )

      a diet bread

  1. the food and drink that a person or animal regularly consumes

    a diet of nuts and water

  2. regular activities or occupations

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. (usually intr) to follow or cause to follow a dietary regimen

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
diet 2 British  
/ ˈdaɪət /

noun

  1. (sometimes capital) a legislative assembly in various countries, such as Japan

  2. Also called: Reichstag(sometimes capital) the assembly of the estates of the Holy Roman Empire

  3. Scots law

    1. the date fixed by a court for hearing a case

    2. a single session of a court

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Inflected Forms

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of diet1

First recorded in 1175–1225; Middle English noun diete “day’s journey, appointed day, way of living,” from Anglo-French, Old French diete, from Latin diaeta, from Greek díaita “way of living, diet,” equivalent to dia- dia- + -aita (akin to aîsa “share, lot”; the verb is derivative of the noun

Origin of diet2

First recorded in 1400–50; late Middle English, from Medieval Latin diēta “public assembly,” the same word as Latin diaeta with sense affected by Latin diēs “day”; see diet 1

Explanation

Diet means the usual food and drink consumed by a person or animal. A healthy diet for your pet is not the same as your diet, so you shouldn't feed your dog all your table scraps. If you limit the number of calories you eat in order to lose weight, or restrict certain foods for your health, you can also call this a diet. If you want to lose 10 pounds by summer, you might have to go on a diet. In certain countries, the word diet, though pronounced the same, has a non-food related meaning: the diet is the legislative branch of the government in countries like Japan.

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Vocabulary lists containing diet

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

When we meet in the pub - drinking diet cola - Barry, from Chester-le-Street, says he reached 25 stone last year at the age of 50.

From BBC Aug. 17, 2026

Here’s how to incorporate the diet into your lifestyle:

From MarketWatch Aug. 16, 2026

Many of the diet’s principles are surprisingly simple, which could explain its enduring popularity and effectiveness and why nutrition experts often describe it as an eating pattern rather than a diet.

From MarketWatch Aug. 16, 2026

He described attempting the keto diet as a “near-psychotic event” brought on by sugar withdrawal, joking that giving someone in his position that much irritability could have geopolitical consequences.

From Salon Aug. 15, 2026

Bunnicula liked his liquid diet so much that the Monroes have kept him on it.

From "Bunnicula" by Deborah Howe and James Howe

Plant based diets support health in several ways, including benefits for the gut, immune system, metabolism, and cardiovascular system.

From Science Daily Aug. 15, 2026

People in Iran said they are limiting spending to essentials such as food, petrol and medicine, dropping meat from their diets, and buying staples one item at a time as their wages lose value.

From The Wall Street Journal Aug. 11, 2026

To ascribe to particular diets and exercise practices that micro-optimize your body is one thing; you may be putting yourself through trials the Jackass guys would never dare, but at least it’s your own body.

From Slate Jul. 31, 2026

The research analysed the impact of the end of sugar rationing in the UK which led to a rapid increase in the amount of sugar in people's diets.

From BBC Jul. 29, 2026

In other tests in which both pheasants and quail were the subjects, the adults produced no eggs whatever if they had been fed insecticide-contaminated diets throughout the year.

From "Silent Spring" by Rachel Carson

“I just couldn’t look like that no matter how much I dieted or went to the gym.”

From The Wall Street Journal May 4, 2026

“Apartments without dining rooms, as if anticipating a future where families disintegrated, compulsively dieted, or ate alone, in front of televisions.”

From Los Angeles Times May 15, 2024

For example, one study revealed that compared with daughters of nondieting women, 5-year-old girls whose mothers dieted were aware of the connection between dieting and thinness.

From Salon Feb. 22, 2024

The sales rep said: "I yo-yo dieted my whole life, for 30 years, and I got my sleeve two years ago."

From BBC Jan. 15, 2024

She binged and dieted and then cycled through it all again.

From "Zeitoun" by Dave Eggers

"The results of our study indicate intermittent fasting could offer an alternative pathway for people who find conventional dieting challenging."

From Science Daily Jul. 8, 2026

These concerns have influenced public opinion and even medical advice, leading some people to believe repeated dieting attempts may ultimately cause more harm than benefit.

From Science Daily May 17, 2026

The loss of lean tissue is similar to weight loss from dieting, but the magnitude over a short period can lead to frailty, instability and lack of coordination, doctors and researchers say.

From The Wall Street Journal May 17, 2026

It found that slimmers who came off weight-loss injections regained their lost pounds four times faster than those who stopped a programme of conventional dieting and exercising.

From BBC Feb. 24, 2026

Most people had the sense not to share a dieting trick with an overweight person, but no one seemed to think it was wrong to share their acne remedies with me.

From "Americanized" by Sara Saedi

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