About
脲 is a modern scientific phono-semantic compound created for chemical terminology. Its left radical 月, a variant of 肉 (flesh/meat), indicates an organic or biological connection. The right component 尿 (urine) serves as both the phonetic element (niào) and the semantic core, identifying the substance from which the chemical is derived. The character was coined to translate "urea", the primary nitrogenous waste in mammalian urine. As a constructed scientific character, it has no ancient textual history and is used exclusively in modern chemistry, biology, and medicine.