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 The spike protein allows the virus to dock onto the cells lining the human upper respiratory system. Mark Johnson, Milwaukee Journal Sentinel, "Citing 'an unexplained illness,' AstraZeneca halts COVID-19 vaccine trials underway in Madison and worldwide," 10 Sep. 2020 That said, nearly every other vaccine is based on the same protein from the SARS-CoV-2 virus. Elizabeth Weise, USA TODAY, "AstraZeneca's COVID-19 vaccine trial has been stopped after an illness. Here's what it means.," 9 Sep. 2020 Another possibility is a Novichok conjugate of serum albumin, the most abundant protein in blood. Richard Stone, Science | AAAS, "How German military scientists likely identified the nerve agent used to attack Alexei Navalny," 8 Sep. 2020 This is based on their analysis of ACE2 receptors, the key protein for virus entry. Carolyn Barber, Fortune, "Everything we know—and don’t know—about human-to-animal COVID transmission," 4 Sep. 2020 The virus has been tweaked to contain the genetic spike protein found in SARS-CoV-2. Kristen Jordan Shamus, Detroit Free Press, "AstraZeneca COVID-19 vaccine trials coming to University of Michigan," 1 Sep. 2020 While a pregnancy test detects a hormone, BinaxNOW looks for an antigen, a tiny portion of the coronavirus protein. Jordan Fabian, Bloomberg.com, "U.S. Buys Almost All Abbott’s $5 Rapid Tests Made This Year," 29 Aug. 2020 While a pregnancy test is designed to detect a hormone, Abbott’s BinaxNOW looks for an antigen, a tiny portion of the coronavirus protein that’s collected from inside the nose. Bloomberg News, oregonlive, "For $5 and in 15 minutes, this COVID-19 test could be a game-changer," 29 Aug. 2020 The key protein used in the vaccine was co-invented by the National Institutes of Health. Washington Post, "Moderna failed to disclose federal support in vaccine patents, researchers say," 28 Aug. 2020

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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Time Traveler for protein

Time Traveler

The first known use of protein was in 1886

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Statistics for protein

Last Updated

21 Sep 2020

Cite this Entry

“Protein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/protein. Accessed 1 Oct. 2020.

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More Definitions for protein

protein

noun
How to pronounce protein (audio) How to pronounce protein (audio)

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

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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