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

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 Thanks to a star ingredient called Alpha Keratin 60ku, a protein extracted from real human hair, my strands feel stronger after each wash. Elizabeth Denton, Allure, "Virtue's New Protein Powder Made My Damaged, Color-Treated Hair Look Like New," 19 Mar. 2019 Mammals would sense a foreign protein, Wilson says. Jocelyn Kaiser, Science | AAAS, "Gene edited monkeys offer hope for heart disease patients," 9 July 2018 Poké is sushi in a bowl where patrons walk up to a counter to pick rice or lettuce, a protein, a sauce, toppings, mix-ins and garnishes, Usui said. Rene Wisely, Detroit Free Press, "Kybun Joya Shoes, sports collectibles, sushi, whiskey fill downtowns," 9 July 2018 For the new study in the journal Cell Chemical Biology, researcher Marcos Pires of Lehigh University and his colleagues combined an existing antibiotic with a protein which stimulates the immune system to attack. Jason Daley, Smithsonian, "New “Immunobiotic” Could Treat Antibiotic-Resistant Superbugs," 6 July 2018 The Hungarians had discovered a protein that brakes the immune system to keep it from attacking a fast-growing invader — the fetus. Marie Mccullough, Philly.com, "Can the abortion pill treat advanced lung cancer? This infertility expert wants to find out," 3 July 2018 She was also required to take a purified protein derivative (PPD) skin test for TB. Libby Solomon, baltimoresun.com, "Government sues Towson home care franchise alleging ADA violation," 28 June 2018 The poliovirus can attach to a protein on the surface of cancer cells. Jonathan Lapook, CBS News, "Trial shows poliovirus may be effective in treating deadly brain cancer glioblastoma," 26 June 2018

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

17 Apr 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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