What does L, D or DL mean?
L is levorotatory (Latin for left) and D is Dextrorotatory (Latin for right). These designations depict the direction of a beam of plane-polarized light through a sample of the product. Compounds with the same molecular weight and structure differing by only D or L are optical isomers. DL forms are a racemic mixture (50 % D, 50% L) of the product.