ENGLISH
REFERENCE

protein

n. C / U
B2 Upper Intermediate Oxford US //ˈpɹoʊˌtin// UK //pɹˈəʊtiːn// pro·tein General-service

n. a natural substance found in foods like meat, beans, and eggs that helps your body grow and stay strong. It is an essential part of a healthy diet because it builds and fixes your muscles.

n. a complex organic compound composed of amino acids, essential for the growth, repair, and maintenance of living cells. It serves as a primary structural component of body tissues such as muscle and hair.


SIMPLE

Chicken and lentils are both high in protein.

CONTEXTUAL

Athletes often consume a high-protein shake after training to help their muscles recover from intense exercise.

COMPLEX

While most people associate protein with animal products, a balanced plant-based diet can provide all the essential amino acids required for human health through a variety of grains and legumes.

Origin

From proto- + -ein. Suggested by Jöns Jacob Berzelius in a letter to Gerardus Johannes Mulder, from French protéine and German Protein, both coined based on Ancient Greek πρωτεῖος (prōteîos, “primary”), from πρῶτος (prôtos, “first”).

Usage

Uncountable when referring to the nutrient in general; countable when referring to specific types of protein molecules in a scientific context.

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