protein

noun, often attributive
pro·​tein | \ ˈprō-ˌtēn How to pronounce protein (audio) also ˈprō-tē-ən How to pronounce protein (audio) \

Definition of protein

1 : any of various naturally occurring extremely complex substances that consist of amino-acid residues joined by peptide bonds, contain the elements carbon, hydrogen, nitrogen, oxygen, usually sulfur, and occasionally other elements (such as phosphorus or iron), and include many essential biological compounds (such as enzymes, hormones, or antibodies)
2 : the total nitrogenous material in plant or animal substances

Examples of protein in a Sentence

You need more protein in your diet. These foods are an excellent source of protein. These foods have all of the essential proteins.
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Recent Examples on the Web

An Impossible Burger has 50 fewer calories, 8 fewer grams of fat; and the same amount of protein. Emily Atkin, The New Republic, "The Promise and Problem of Fake Meat," 7 June 2019 That’s why Cote likes to pack non-perishable snacks like nuts, protein bars or low-sodium jerky. Stephanie Emma Pfeffer, PEOPLE.com, "Experts Share Their Best Tips on How to Avoid Vacation Weight Gain," 6 June 2019 The findings held even when diets contained high levels of saturated fat, which increased blood cholesterol to the same extent as all three protein sources. NBC News, "When it comes to cholesterol, is chicken as bad as red meat?," 4 June 2019 Shoot for around 15% of calories from high-fat protein sources like those below. Karla Walsh, Woman's Day, "The Ultimate Keto Diet Foods List of What You Can (and Can't) Eat," 28 Dec. 2018 Hyde's ideal morning-after feast is a protein source like eggs, yogurt, or cottage cheese with a mix of leafy vegetables and healthy carbs like berries. Jenna Rosenstein, Harper's BAZAAR, "The Holidays Are Coming—Here's How To Get Back On Track After a Big Meal," 19 Oct. 2018 Choose heart-healthy protein sources like cottage cheese, yogurt, fatty fish, poultry, and whole eggs. Carly Graf, Outside Online, "The Foods You Should Be Eating at Every Age," 28 June 2018 So instead, start your day off with a protein and fiber-rich breakfast. Jenna Rosenstein, Harper's BAZAAR, "The Holidays Are Coming—Here's How To Get Back On Track After a Big Meal," 19 Oct. 2018 Try to choose slow burning carbs, like whole-wheat bread and pasta and brown rice over refined ones when possible, and combine them with protein, fiber, and healthy fats. Suzannah Weiss, Glamour, "9 Foods to Avoid If You're Trying to Get Pregnant," 17 Apr. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'protein.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of protein

1886, in the meaning defined at sense 1

History and Etymology for protein

French protéine, from Late Greek prōteios primary, from Greek prōtos first — more at proto-

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Statistics for protein

Last Updated

12 Jun 2019

Look-up Popularity

Time Traveler for protein

The first known use of protein was in 1886

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More Definitions for protein

protein

noun

English Language Learners Definition of protein

: a substance found in foods (such as meat, milk, eggs, and beans) that is an important part of the human diet

protein

noun
pro·​tein | \ ˈprō-ˌtēn How to pronounce protein (audio) \

Kids Definition of protein

: a nutrient found in food (as meat, milk, eggs, and beans) that is made up of many amino acids joined together, is a necessary part of the diet, and is essential for normal cell structure and function

protein

noun, often attributive
pro·​tein | \ ˈprō-ˌtēn How to pronounce protein (audio) , ˈprōt-ē-ən How to pronounce protein (audio) \

Medical Definition of protein

1 : any of numerous naturally occurring extremely complex substances (as an enzyme or antibody) that consist of amino acid residues joined by peptide bonds, contain the elements carbon, hydrogen, nitrogen, oxygen, usually sulfur, and occasionally other elements (as phosphorus or iron), that are essential constituents of all living cells, that are synthesized from raw materials by plants but assimilated as separate amino acids by animals, that are both acidic and basic and usually colloidal in nature although many have been crystallized, and that are hydrolyzable by acids, alkalies, proteolytic enzymes, and putrefactive bacteria to polypeptides, to simpler peptides, and ultimately to alpha-amino acids
2 : the total nitrogenous material in plant or animal substances especially : crude protein

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More from Merriam-Webster on protein

Rhyming Dictionary: Words that rhyme with protein

Spanish Central: Translation of protein

Nglish: Translation of protein for Spanish Speakers

Britannica English: Translation of protein for Arabic Speakers

Britannica.com: Encyclopedia article about protein

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