protease

noun

pro·​te·​ase ˈprō-tē-ˌās 

-ˌāz

: any of numerous enzymes that hydrolyze proteins and are classified according to the most prominent functional group (such as serine or cysteine) at the active site

called also proteinase

Examples of protease in a Sentence

Recent Examples on the Web

Lipase breaks down fats, amylase breaks down carbs, and proteases and peptidases both break down proteins, to name a few. — Caroline Tien, SELF, 11 Mar. 2026

In the stomach, this continues as acids and enzymes called proteases turn protein molecules into smaller chains of amino acids. — Mark Gurarie, Verywell Health, 18 Aug. 2025

The compounds target a protein that is the Achilles heel for coronaviruses, the coronavirus main protease, Mpro. — IEEE Spectrum, 4 Dec. 2020

These enzymes break down the protein components of the grass (protease) and the cellulose fibers (cellulase), releasing the dirt and green chlorophyll trapped in the garment's fibers. — Mary Marlowe Leverette, Southern Living, 14 June 2026

Word History

Etymology

borrowed from French protéase, from protéine protein + -ase -ase

Note: The French term was probably introduced by the Italian microbiologist and philosopher Giovanni Malfitano (1872-1941) in "Sur le protéase de l'Aspergillus niger," Annales de l'Institut Pasteur, tome quatorzième (1900), p. 420. The term protease was used in English without attribution to Malfitano and perhaps coined independently by the British botanist Sydney Howard Vines (1849-1934) in "Proteolytic Enzymes in Plants," Annals of Botany, vol. 17, no. 65 (January, 1903), p. 237.

First Known Use

1903, in the meaning defined above

Phrases Containing protease

• protease inhibitor

Rhymes for protease

• ablaze
• airways
• allays
• always
• amaze
• anglaise
• appraise
• archways
• arrays
• ashtrays
• assays
• atpase

Medical Definition

protease

noun

pro·​te·​ase ˈprōt-ē-ˌās, -ˌāz 

: any of numerous enzymes that hydrolyze proteins and are classified according to the most prominent functional group (as serine or cysteine) at the active site

called also proteinase

compare peptidase