He derived the term from the Greek word "protos" meaning "of first importance" or "primary." This was because Berzelius recognized proteins as essential and fundamental components of living organisms.

While Berzelius first used the term, other scientists had previously observed and studied these substances. For example, in 1838, Gerardus Johannes Mulder identified a class of organic compounds containing carbon, hydrogen, oxygen, and nitrogen, which he called "proteïne" after the Greek word "proteios," meaning "primary." This discovery laid the groundwork for Berzelius's subsequent coining of the term "protein."