What does urea mean?
Urea is the chemical name for a simple organic compound, formula NH₂CONH₂, with two important roles in English usage. In the body, the liver converts toxic ammonia into urea, which the kidneys excrete in urine; consequently, blood urea nitrogen is a familiar laboratory test. Outside medicine, manufactured urea is a concentrated nitrogen fertilizer and an ingredient in animal feed and urea-formaldehyde resins. The word is normally technical rather than conversational, but it has a distinctive history: in 1820, Friedrich Wöhler synthesized urea from ammonium cyanate, helping undermine vitalism, the belief that only living organisms could produce organic compounds. Urea is also called carbamide, making it more recognizable in chemical and pharmaceutical contexts. Knowing the word therefore connects an ordinary biological waste product with agriculture, industrial chemistry, and one of the landmark experiments in the development of modern chemistry.
nounUrea is a colorless, crystalline organic compound, NH₂CONH₂, that is the principal nitrogen-containing waste product of mammalian metabolism. It is also manufactured for use in fertilizers, animal feed, resins, and pharmaceuticals.
- The organic compound NH₂CONH₂, whether occurring naturally or produced industrially.
- Urea used as a concentrated nitrogen fertilizer or as an additive in animal feed.
- The nitrogen-containing waste substance produced by the liver and excreted by the kidneys in urine.
"The liver converts ammonia into urea, which the kidneys then filter from the blood and excrete in urine."
"The liver converts toxic ammonia into urea, which the kidneys remove from the blood."
"Urea-formaldehyde resin is widely used in making engineered wood products."
Urea is normally an uncountable mass noun. The plural “ureas” is limited mainly to chemistry, where it can refer to related compounds or individual members of a series of urea derivatives.
"The researchers compared the properties of several substituted ureas."
In 1820, Friedrich Wöhler synthesized urea in the laboratory, helping undermine vitalism—the belief that only living organisms could produce organic compounds.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does urea come from?
The word was coined in the early nineteenth century from Greek οὖρον (ouron), meaning “urine,” because crystalline urea had been isolated from urine. Greek οὖρον and Latin urina are cognate, and related English words include urinary, urinate, and urology. Urea is also historically associated with Wöhler's 1820 synthesis of the compound from ammonium cyanate.
Related word forms
How urea is actually used
Urea is primarily a technical term in chemistry, medicine, agriculture, and biology. It is also called carbamide, particularly in chemical and pharmaceutical contexts, and its pronunciation is essentially the same in British and American English.
Easily confused with urea
Urea is a neutral organic compound containing one carbon atom, whereas uric acid is a purine-derived organic acid.