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

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 With a visible protein, Smith realized that scientists could train antibodies to target it with precision. David Grossman, Popular Mechanics, "The 2018 Nobels in Chemistry Made Evolution Work For Us," 3 Oct. 2018 Do not serve marinades that have come in contact with raw proteins. Becky Krystal, sacbee, "If you’re in the mood to marinate meat, soak up these tips," 26 June 2018 Instead, the transposon’s RNA teams up with two proteins to allow the two-celled embryos to continue developing. Mitch Leslie, Science | AAAS, "Don’t call it junk—This ‘jumping’ gene may be why you made it past an embryo," 21 June 2018 Their plan involves eating six small meals per day to kick start weight loss, and focuses primarily on portion control, healthy snacking, and cooking meals with lean proteins. Madison Roberts, ajc, "‘Cake Boss’ Buddy Valastro has lost a lot of weight. Here is how he did it," 20 June 2018 Nuts are a good source of unsaturated fats as well as fiber, protein and a variety of minerals and antioxidants. Consumer Reports, Washington Post, "From oatmeal to sardines, 7 foods that really can help hearts stay healthy," 7 May 2018 Mornings begin with a cup of English breakfast tea and a green protein smoothie. Jen Murphy, WSJ, "The Fitness Plan for Serious Schmoozers," 16 Feb. 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

15 May 2019

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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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