protein

noun, often attributive
pro·tein | \ ˈprō-ˌtēn also ˈprō-tē-ən \

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

This includes foods higher in protein and fiber, like meat, fish, avocados, veggies, potatoes, and whole grains. Nick Heil, Outside Online, "Blame Your Junk Food Cravings on Your Unhealthy Brain," 3 July 2018 Once stabilized, Kirnon puts those fats and proteins to work building an impossibly rich broth. Ali Bouzari, San Francisco Chronicle, "Housemade: The science behind the skillets at Miss Ollie’s in Oakland," 16 May 2018 The skillets feature a combination of egg, another protein and vegetables over a bed of hash browns. Andy Staples, SI.com, "How 'Scheduling for Success' Can Help the Pac-12 Keep Pace in the Playoff Era," 7 May 2018 The most recent success has been hemoglobin (by [Max Ferdinand] Perutz); the model of this protein contains 10,000 atoms. Daniel C. Schlenoff, Scientific American, "“Foul Treachery” of Trotsky and Lenin in 1918; Phineas Gage’s Brain in 1868," 13 July 2018 The latest promising candidate is TGF-beta, a thorny collection of proteins that regulates a host of bodily functions. Damian Garde, STAT, "Biopharma has a new big idea for making cancer immunotherapy work better," 5 July 2018 Or Summit could be used for complex DNA analysis or to figure out the structure of proteins. Avery Thompson, Popular Mechanics, "The United States Has the World's Fastest Supercomputer Again," 8 June 2018 Such modifications, which serve to regulate the activity of genes, are chemical alterations of a cell’s DNA and of the proteins in which that DNA is packed. The Economist, "HIV+ volunteers are bequeathing their organs to a new project," 31 May 2018 Plants crave nitrogen, used in building proteins and DNA, and ammonia delivers it in a biologically available form. Robert F. Service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 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

4 Sep 2018

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 \

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 , ˈprōt-ē-ən \

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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