/euh lan"toh in/ , n. Biochem., Pharm.
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.
[ 1835-45; ALLANTO(IS) + -IN 2 ; so named because it is found in the fluid of the allantois ]