n (Chemistry) chem a type of isomer that differs in the spatial arrangement of atoms in the molecule, but is not a mirror image; a stereoisomer that is not an enantiomerTranslations
diastereoisomer
diastereoisomer
[¦dī·ə‚ster·ē·ō′ī·sə· mər] (organic chemistry) One of a pair of optical isomers which are not mirror images of each other. Also known as diastereomer.