a white, crystalline, slightly water-soluble glucoside, C15H16O9, obtained from the bark of the common horse chestnut and used chiefly in skin preparations as a protective against sunburn.
Main Entry: es·cu·lin Variant: oraes·cu·lin/'es-ky&-l&n/ Function: noun : a glucosideC15H16O9 from the inner bark of the horse chestnut (Aesculus hippocastaneum) and roots of the yellow jessamine (Gelsemium sempervirens) that absorbsultraviolet rays
[es-kyuh-lin] 
kyə