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

In mice with Alzheimer’s disease, the same protein contained in Leukine cleared amyloid debris from the brain while reversing memory loss. Washington Post, The Denver Post, "Colorado Alzheimer’s researchers shift focus after failures; begin testing leukemia medicine as treatment," 6 July 2019 Inside the feather’s barbules, layers of melanosomes and a type of the structural protein keratin can scatter incoming light in such a way that only certain colors reflect back out. Michael Greshko, National Geographic, "First blue feathers found on a fossilized bird," 25 June 2019 Customers can order the protein in burritos or burrito bowls. Ava Garcia, azcentral, "Your guide to fast food restaurants with Beyond and Impossible burgers in metro Phoenix," 24 June 2019 Those mites feed on the bees’ fats and that’s where the insects store protein and center their immune response. Seth Borenstein, Twin Cities, "Survey sees biggest US honeybee winter die-off yet," 19 June 2019 His research focuses on repairing dystrophin, the main protein missing in people with Duchenne. Orla Mccaffrey, Dallas News, "Boston research company bets on UT Southwestern researcher's gene therapy," 18 June 2019 The company has patented dozens of molecular combinations of the natural silk protein since filing its first application in 2014. Kim Bhasin, Fortune, "Chanel Invests in Boston Startup Making Sustainable Silk," 11 June 2019 Limpets, easy to spot and pry from their perches, turned out to be the protein of choice for many students’ first meal. Susan Shain, The Atlantic, "When Your Final Exam Is Surviving the Wilderness," 5 June 2019 Research found that some people who had HIV infections that progressed slowly often had mutations in CCR5, often a specific mutation called ∆32, which causes severe damage to the protein. John Timmer, Ars Technica, "Target of first human gene editing cuts life expectancy short," 5 June 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

10 Jul 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

Comments on protein

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