Arginin

Part of speech: noun

Definitions

1. A basic amino acid that the body uses to build proteins and that plays a role in releasing hormones and removing ammonia
2. An amino acid found in many dietary proteins that helps form the building blocks of protein and supports wound healing and immune function
3. A nonessential amino acid that cells use to make proteins, which also serves as a precursor for nitric oxide and urea production

Etymology: Arginine is named after silver. The German chemist who first isolated it gave it a name from the Greek "argyros," meaning silver, probably because of the silvery salts it forms with certain acids. The "-ine" ending is the standard chemical suffix for nitrogen-containing compounds, which is why it sits alongside other amino acid names like lysine and glycine. Its name is older than its role in biology. The compound was first obtained from plant material, and only later did chemists recognize it as one of the building blocks of proteins, with a nitrogen-rich side chain that makes it unusually basic. Its name has stayed fixed since then, so the Greek word for silver is still embedded in a molecule found in nearly every living cell.