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allantoin

American  
[uh-lan-toh-in] / əˈlæn toʊ ɪn /

noun

Biochemistry, Pharmacology.
  1. a white powder, C 4 H 6 N 4 O 3 , produced by oxidation of uric acid and the major excretory product of purine degradation in many vertebrates: used medicinally to heal skin ulcers and in lotions, lipsticks, etc., for its soothing effect.


allantoin British  
/ ˌælənˈtəʊɪn /

noun

  1. a substance derived from the secretions of snails and contained in some plants, used in skin care products and valued for its soothing properties

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of allantoin

1835–45; allanto(is) + -in 2; so named because it is found in the fluid of the allantois

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Thanks to allantoin, a substance it contains that causes cells to multiply, healers have used it since ancient times to set bones, close wounds and treat burns.

From Washington Post

Pro Vitamin B keeps skin moisturized and nourished, while Allantoin soothes and calms flare-ups.

From New York Times

Dr. Tuhina Neogi, a rheumatologist at the Boston University School of Medicine, explained that humans lack the enzyme uricase, present in most other animals, and thus are unable to convert urate into allantoin, the soluble end-product of purine metabolism.

From New York Times

Wounds and ulcers promptly heal under the bland influence of a remarkable chemical, allantoin, which such urine contains.

From Time Magazine Archive

Allantoin also occurs in beets and bruisewort, favorite folk remedies for cuts and ulcers.

From Time Magazine Archive