# protein

Pronunciation: US say "PROH-teen" /ˈpɹoʊ.tiːn/; UK say "PROH-tee-in" /ˈpɹəʊ.ti.ɪn/

## Noun

1. One of the three major classes of food energy, supplying about 4 calories per gram and abundant in meat and some vegetables such as legumes.
   - Simple: One of the three main kinds of food the body uses for energy and growth, found in meat, eggs, and beans.
   - _Nutritionists recommend balancing protein with carbohydrates and fats at each meal._
   - _A diet too low in protein can lead to muscle loss over time._
2. Any of many large, complex molecules made of one or more long chains of amino acids linked together by peptide bonds.
   - Simple: A large natural molecule made of long chains of tiny building blocks called amino acids.
   - _Each protein folds into a specific shape that determines its function._
   - _Enzymes are proteins that speed up chemical reactions in the cell._
3. A food rich in protein, often a meat or a meat substitute such as tofu or beans.
   - Simple: A food, usually meat or a meat substitute, that is high in protein.
   - _The chef paired a hearty protein with roasted vegetables._
   - _Vegetarian diets rely on proteins like lentils, tofu, and chickpeas._

## Origin

Formed from proto- + -ein, the word was suggested by Jöns Jacob Berzelius in a letter to Gerardus Johannes Mulder. It came from French protéine and German Protein, both coined from Ancient Greek πρωτεῖος (prōteîos, 'primary'), from πρῶτος (prôtos, 'first').

Source: DictionaryAI, https://dictionaryai.com/define/protein (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).