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 South African variant has more than 20 mutations, including several affecting the spike protein. Sarah Toy, WSJ, "New Covid-19 Strains: What Scientists Know About Coronavirus Variants," 1 Jan. 2021 The AstraZeneca vaccine uses a harmless cold virus that typically infects chimpanzees to deliver to the body’s cells the genetic code of the spike protein that dots the outside of the coronavirus. Author: William Booth, Karla Adam, Anchorage Daily News, "U.K. is first country to authorize Oxford-AstraZeneca coronavirus vaccine," 30 Dec. 2020 Studies of the milder human coronaviruses show that the spike protein can evolve to evade the immune system within a decade or two. Ed Yong, The Atlantic, "Pandemic Year Two," 29 Dec. 2020 These shots are made with a brand-new technology that injects a piece of genetic code for the spike protein that coats the coronavirus. Time, "More COVID-19 Vaccines Are in the Pipeline as the U.S. Effort Ramps Up," 29 Dec. 2020 While the mRNA vaccines rolled out by Pfizer and Moderna rely on the body's cells producing antigens to hone the body's defenses, Novavax manufactures its own antigens mimicking the virus' spike protein. Alexander Tin, CBS News, "COVID-19 vaccine from Novavax is latest to enter Phase 3 trial in U.S.," 29 Dec. 2020 These shots are made with a brand-new technology that injects a piece of genetic code for the spike protein that coats the coronavirus. Lauran Neergaard, chicagotribune.com, "More COVID-19 vaccines in the pipeline as US effort ramps up," 28 Dec. 2020 This is in part due to the fact that there are multiple sites on the spike protein that antibodies can target to neutralize the virus. William Petri, The Conversation, "Should pregnant women get the COVID-19 vaccine? Will it protect against asymptomatic infections and mutated viruses? An immunologist answers 3 questions," 23 Dec. 2020 Two of the viral mutations developed in genes that code for the spike protein. Maya Wei-haas, Science, "Why new coronavirus variants 'suddenly arose' in the U.K. and South Africa," 23 Dec. 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

13 Jan 2021

Cite this Entry

“Protein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/protein. Accessed 16 Jan. 2021.

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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

Comments on protein

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